A. Wölfl, Norbert Siegmund, S. Apel, H. Kosch, Johann Krautlager, Guillermo Weber-Urbina
We report on our experience with enhancing the data-management component in the avionics software of the NH90 helicopter at Airbus Helicopters. We describe challenges regarding the evolution of avionics software by means of real-world evolution scenarios that arise in industrial practice. A key role plays a legally-binding certification process, called qualification, which is responsible for most of the development effort and cost. To reduce effort and cost, we propose a novel generative approach to develop qualifiable avionics software by combining model-based and product-line technology. Using this approach, we have already generated code that is running on the NH90 helicopter and that is in the process of replacing the current system code. Based on an interview with two professional developers at Airbus and an analysis of the software repository of the NH90, we systematically compare our approach with established development approaches in the avionics domain, in terms of implementation and qualification effort.
{"title":"Generating Qualifiable Avionics Software: An Experience Report (E)","authors":"A. Wölfl, Norbert Siegmund, S. Apel, H. Kosch, Johann Krautlager, Guillermo Weber-Urbina","doi":"10.1109/ASE.2015.35","DOIUrl":"https://doi.org/10.1109/ASE.2015.35","url":null,"abstract":"We report on our experience with enhancing the data-management component in the avionics software of the NH90 helicopter at Airbus Helicopters. We describe challenges regarding the evolution of avionics software by means of real-world evolution scenarios that arise in industrial practice. A key role plays a legally-binding certification process, called qualification, which is responsible for most of the development effort and cost. To reduce effort and cost, we propose a novel generative approach to develop qualifiable avionics software by combining model-based and product-line technology. Using this approach, we have already generated code that is running on the NH90 helicopter and that is in the process of replacing the current system code. Based on an interview with two professional developers at Airbus and an analysis of the software repository of the NH90, we systematically compare our approach with established development approaches in the avionics domain, in terms of implementation and qualification effort.","PeriodicalId":6586,"journal":{"name":"2015 30th IEEE/ACM International Conference on Automated Software Engineering (ASE)","volume":"42 1","pages":"726-736"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84620081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Language fuzzing is a bug-finding technique for testing compilers and interpreters, its effectiveness depends upon the ability to automatically generate valid programs in the language under test. Despite the proven success of language fuzzing, there is a severe lack of tool support for fuzzing statically-typed languages with advanced type systems because existing fuzzing techniques cannot effectively and automatically generate well-typed programs that use sophisticated types. In this work we describe how to automatically generate well-typed programs that use sophisticated type systems by phrasing the problem of well-typed program generation in terms of Constraint Logic Programming (CLP). In addition, we describe how to specifically target the typechecker implementation for testing, unlike all existing work which ignores the typechecker. We focus on typechecker precision bugs, soundness bugs, and consistency bugs. We apply our techniques to Rust, a complex, industrial-strength language with a sophisticated type system.
{"title":"Fuzzing the Rust Typechecker Using CLP (T)","authors":"Kyle Dewey, Jared Roesch, B. Hardekopf","doi":"10.1109/ASE.2015.65","DOIUrl":"https://doi.org/10.1109/ASE.2015.65","url":null,"abstract":"Language fuzzing is a bug-finding technique for testing compilers and interpreters, its effectiveness depends upon the ability to automatically generate valid programs in the language under test. Despite the proven success of language fuzzing, there is a severe lack of tool support for fuzzing statically-typed languages with advanced type systems because existing fuzzing techniques cannot effectively and automatically generate well-typed programs that use sophisticated types. In this work we describe how to automatically generate well-typed programs that use sophisticated type systems by phrasing the problem of well-typed program generation in terms of Constraint Logic Programming (CLP). In addition, we describe how to specifically target the typechecker implementation for testing, unlike all existing work which ignores the typechecker. We focus on typechecker precision bugs, soundness bugs, and consistency bugs. We apply our techniques to Rust, a complex, industrial-strength language with a sophisticated type system.","PeriodicalId":6586,"journal":{"name":"2015 30th IEEE/ACM International Conference on Automated Software Engineering (ASE)","volume":"61 1","pages":"482-493"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80587377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stakeholders and organisations are increasingly looking for long-lived software. As architectures have a profound effect on the operational life-time of the software and the quality of the service provision, architectural stability could be considered a primary criterion towards achieving the long-livety of the software. Architectural stability is envisioned as the next step in quality attributes, combining many inter-related qualities. This research suggests the notion of behavioural stability as a primary criterion for evaluating whether the architecture maintains achieving the expected quality attributes, maintaining architecture robustness, and evaluating how well the architecture accommodates run-time evolutionary changes. The research investigates the notion of architecture stability at run-time in the context of self-adaptive software architectures. We expect to define, characterise and analyse this intuitive concept, as well as identify the consequent trade-offs to be dynamically managed and enhance the self-adaptation process for a long-lived software.
{"title":"Stability of Self-Adaptive Software Architectures","authors":"M. Salama","doi":"10.1109/ASE.2015.93","DOIUrl":"https://doi.org/10.1109/ASE.2015.93","url":null,"abstract":"Stakeholders and organisations are increasingly looking for long-lived software. As architectures have a profound effect on the operational life-time of the software and the quality of the service provision, architectural stability could be considered a primary criterion towards achieving the long-livety of the software. Architectural stability is envisioned as the next step in quality attributes, combining many inter-related qualities. This research suggests the notion of behavioural stability as a primary criterion for evaluating whether the architecture maintains achieving the expected quality attributes, maintaining architecture robustness, and evaluating how well the architecture accommodates run-time evolutionary changes. The research investigates the notion of architecture stability at run-time in the context of self-adaptive software architectures. We expect to define, characterise and analyse this intuitive concept, as well as identify the consequent trade-offs to be dynamically managed and enhance the self-adaptation process for a long-lived software.","PeriodicalId":6586,"journal":{"name":"2015 30th IEEE/ACM International Conference on Automated Software Engineering (ASE)","volume":"27 1","pages":"886-889"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83221268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In today's web applications, JavaScript code interacts with the Document Object Model (DOM) at runtime. This runtime interaction between JavaScript and the DOM is error-prone and challenging to test. In order to unit test a JavaScript function that has read/write DOM operations, a DOM instance has to be provided as a test fixture. This DOM fixture needs to be in the exact structure expected by the function under test. Otherwise, the test case can terminate prematurely due to a null exception. Generating these fixtures is challenging due to the dynamic nature of JavaScript and the hierarchical structure of the DOM. We present an automated technique, based on dynamic symbolic execution, which generates test fixtures for unit testing JavaScript functions. Our approach is implemented in a tool called ConFix. Our empirical evaluation shows that ConFix can effectively generate tests that cover DOM-dependent paths. We also find that ConFix yields considerably higher coverage compared to an existing JavaScript input generation technique.
{"title":"Generating Fixtures for JavaScript Unit Testing (T)","authors":"A. M. Fard, A. Mesbah, Eric Wohlstadter","doi":"10.1109/ASE.2015.26","DOIUrl":"https://doi.org/10.1109/ASE.2015.26","url":null,"abstract":"In today's web applications, JavaScript code interacts with the Document Object Model (DOM) at runtime. This runtime interaction between JavaScript and the DOM is error-prone and challenging to test. In order to unit test a JavaScript function that has read/write DOM operations, a DOM instance has to be provided as a test fixture. This DOM fixture needs to be in the exact structure expected by the function under test. Otherwise, the test case can terminate prematurely due to a null exception. Generating these fixtures is challenging due to the dynamic nature of JavaScript and the hierarchical structure of the DOM. We present an automated technique, based on dynamic symbolic execution, which generates test fixtures for unit testing JavaScript functions. Our approach is implemented in a tool called ConFix. Our empirical evaluation shows that ConFix can effectively generate tests that cover DOM-dependent paths. We also find that ConFix yields considerably higher coverage compared to an existing JavaScript input generation technique.","PeriodicalId":6586,"journal":{"name":"2015 30th IEEE/ACM International Conference on Automated Software Engineering (ASE)","volume":"21 1","pages":"190-200"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85113352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Omar Inverso, Truc L. Nguyen, B. Fischer, S. L. Torre, G. Parlato
Lazy-CSeq is a context-bounded verification tool for sequentially consistent C programs using POSIX threads. It first translates a multi-threaded C program into a bounded nondeterministic sequential C program that preserves bounded reachability for all round-robin schedules up to a given number of rounds. It then reuses existing high-performance bounded model checkers as sequential verification backends. Lazy-CSeq handles the full C language and the main parts of the POSIX thread API, such as dynamic thread creation and deletion, and synchronization via thread join, locks, and condition variables. It supports assertion checking and deadlock detection, and returns counterexamples in case of errors. Lazy-CSeq outperforms other concurrency verification tools and has won the concurrency category of the last two SV-COMP verification competitions.
{"title":"Lazy-CSeq: A Context-Bounded Model Checking Tool for Multi-threaded C-Programs","authors":"Omar Inverso, Truc L. Nguyen, B. Fischer, S. L. Torre, G. Parlato","doi":"10.1109/ASE.2015.108","DOIUrl":"https://doi.org/10.1109/ASE.2015.108","url":null,"abstract":"Lazy-CSeq is a context-bounded verification tool for sequentially consistent C programs using POSIX threads. It first translates a multi-threaded C program into a bounded nondeterministic sequential C program that preserves bounded reachability for all round-robin schedules up to a given number of rounds. It then reuses existing high-performance bounded model checkers as sequential verification backends. Lazy-CSeq handles the full C language and the main parts of the POSIX thread API, such as dynamic thread creation and deletion, and synchronization via thread join, locks, and condition variables. It supports assertion checking and deadlock detection, and returns counterexamples in case of errors. Lazy-CSeq outperforms other concurrency verification tools and has won the concurrency category of the last two SV-COMP verification competitions.","PeriodicalId":6586,"journal":{"name":"2015 30th IEEE/ACM International Conference on Automated Software Engineering (ASE)","volume":"1 1","pages":"807-812"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87362129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yanyan Jiang, Du Li, Chang Xu, Xiaoxing Ma, Jian Lu
Inter-thread shared memory dependences are crucial to understanding the behavior of concurrent systems, as such dependences are the cornerstone of time-travel debugging and further predictive trace analyses. To enable effective and efficient shared memory dependence tracing, we present an optimistic scheme addressing the challenge of capturing exact dependences between unsynchronized events to reduce the probe effect of program instrumentation. Specifically, our approach achieved a wait-free fast path for thread-local reads on x86-TSO relaxed memory systems, and simultaneously achieved precise tracing of exact read-after-write, write-after-write and write-after-read dependences on the fly. We implemented an open-source RWTrace tool, and evaluation results show that our approach not only achieves efficient shared memory dependence tracing, but also scales well on a multi-core computer system.
{"title":"Optimistic Shared Memory Dependence Tracing (T)","authors":"Yanyan Jiang, Du Li, Chang Xu, Xiaoxing Ma, Jian Lu","doi":"10.1109/ASE.2015.11","DOIUrl":"https://doi.org/10.1109/ASE.2015.11","url":null,"abstract":"Inter-thread shared memory dependences are crucial to understanding the behavior of concurrent systems, as such dependences are the cornerstone of time-travel debugging and further predictive trace analyses. To enable effective and efficient shared memory dependence tracing, we present an optimistic scheme addressing the challenge of capturing exact dependences between unsynchronized events to reduce the probe effect of program instrumentation. Specifically, our approach achieved a wait-free fast path for thread-local reads on x86-TSO relaxed memory systems, and simultaneously achieved precise tracing of exact read-after-write, write-after-write and write-after-read dependences on the fly. We implemented an open-source RWTrace tool, and evaluation results show that our approach not only achieves efficient shared memory dependence tracing, but also scales well on a multi-core computer system.","PeriodicalId":6586,"journal":{"name":"2015 30th IEEE/ACM International Conference on Automated Software Engineering (ASE)","volume":"65 1","pages":"524-534"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89142671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Due to the exponential increase in the number ofmobile devices being used to access the World Wide Web, it iscrucial that Web sites are functional and user-friendly across awide range of Web-enabled devices. This necessity has resulted in the introduction of responsive Web design (RWD), which usescomplex cascading style sheets (CSS) to fluidly modify a Web site's appearance depending on the viewport width of the device in use. Although existing tools may support the testing of responsive Web sites, they are time consuming and error-prone to use because theyrequire manual screenshot inspection at specified viewport widths. Addressing these concerns, this paper presents a method thatcan automatically detect potential layout faults in responsively designed Web sites. To experimentally evaluate this approach, weimplemented it as a tool, called ReDeCheck, and applied itto 5 real-world web sites that vary in both their approach toresponsive design and their complexity. The experiments revealthat ReDeCheck finds 91% of the inserted layout faults.
{"title":"Automatic Detection of Potential Layout Faults Following Changes to Responsive Web Pages (N)","authors":"Thomas A. Walsh, Phil McMinn, G. M. Kapfhammer","doi":"10.1109/ASE.2015.31","DOIUrl":"https://doi.org/10.1109/ASE.2015.31","url":null,"abstract":"Due to the exponential increase in the number ofmobile devices being used to access the World Wide Web, it iscrucial that Web sites are functional and user-friendly across awide range of Web-enabled devices. This necessity has resulted in the introduction of responsive Web design (RWD), which usescomplex cascading style sheets (CSS) to fluidly modify a Web site's appearance depending on the viewport width of the device in use. Although existing tools may support the testing of responsive Web sites, they are time consuming and error-prone to use because theyrequire manual screenshot inspection at specified viewport widths. Addressing these concerns, this paper presents a method thatcan automatically detect potential layout faults in responsively designed Web sites. To experimentally evaluate this approach, weimplemented it as a tool, called ReDeCheck, and applied itto 5 real-world web sites that vary in both their approach toresponsive design and their complexity. The experiments revealthat ReDeCheck finds 91% of the inserted layout faults.","PeriodicalId":6586,"journal":{"name":"2015 30th IEEE/ACM International Conference on Automated Software Engineering (ASE)","volume":"73 1","pages":"709-714"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88330689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PHP allows the names of variables, classes, functions, methods, and properties to be given dynamically, as expressions that, when evaluated, return an identifier as a string. While this provides greater flexibility for programmers, it also makes PHP programs harder to precisely analyze and understand. In this paper we present a number of patterns designed to recognize idiomatic uses of these features that can be statically resolved to a precise set of possible names. We then evaluate these patterns across a corpus of 20 open-source systems totaling more than 3.7 million lines of PHP, showing how often these patterns occur in actual PHP code, demonstrating their effectiveness at statically determining the names that can be used at runtime, and exploring anti-patterns that indicate when the identifier computation is truly dynamic.
{"title":"Variable Feature Usage Patterns in PHP (T)","authors":"M. Hills","doi":"10.1109/ASE.2015.72","DOIUrl":"https://doi.org/10.1109/ASE.2015.72","url":null,"abstract":"PHP allows the names of variables, classes, functions, methods, and properties to be given dynamically, as expressions that, when evaluated, return an identifier as a string. While this provides greater flexibility for programmers, it also makes PHP programs harder to precisely analyze and understand. In this paper we present a number of patterns designed to recognize idiomatic uses of these features that can be statically resolved to a precise set of possible names. We then evaluate these patterns across a corpus of 20 open-source systems totaling more than 3.7 million lines of PHP, showing how often these patterns occur in actual PHP code, demonstrating their effectiveness at statically determining the names that can be used at runtime, and exploring anti-patterns that indicate when the identifier computation is truly dynamic.","PeriodicalId":6586,"journal":{"name":"2015 30th IEEE/ACM International Conference on Automated Software Engineering (ASE)","volume":"40 1","pages":"563-573"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91346944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael Vierhauser, Rick Rabiser, P. Grünbacher, Jürgen Thanhofer-Pilisch
The behavior of systems of systems (SoS) emerges only fully during operation and is hard to predict. SoS thus need to be monitored at runtime to detect deviations from important requirements. However, existing approaches for checking runtime behavior and performance characteristics are limited with respect to the kinds of checks and the types of technologies supported, which impedes their use in industrial SoS. In this tool demonstration paper we describe the ReMinds tool suite for runtime monitoring of SoS developed in response to industrial monitoring scenarios. ReMinds provides comprehensive tool support for instrumenting systems, extracting events and data at runtime, defining constraints to check expected behavior and properties, and visualizing constraint violations to facilitate diagnosis.
{"title":"The ReMinds Tool Suite for Runtime Monitoring of Systems of Systems","authors":"Michael Vierhauser, Rick Rabiser, P. Grünbacher, Jürgen Thanhofer-Pilisch","doi":"10.1109/ASE.2015.91","DOIUrl":"https://doi.org/10.1109/ASE.2015.91","url":null,"abstract":"The behavior of systems of systems (SoS) emerges only fully during operation and is hard to predict. SoS thus need to be monitored at runtime to detect deviations from important requirements. However, existing approaches for checking runtime behavior and performance characteristics are limited with respect to the kinds of checks and the types of technologies supported, which impedes their use in industrial SoS. In this tool demonstration paper we describe the ReMinds tool suite for runtime monitoring of SoS developed in response to industrial monitoring scenarios. ReMinds provides comprehensive tool support for instrumenting systems, extracting events and data at runtime, defining constraints to check expected behavior and properties, and visualizing constraint violations to facilitate diagnosis.","PeriodicalId":6586,"journal":{"name":"2015 30th IEEE/ACM International Conference on Automated Software Engineering (ASE)","volume":"20 1","pages":"777-782"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74974749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Understanding how performance varies across a large number of variants of a configurable software system is important for helping stakeholders to choose a desirable variant. Given a software system with n optional features, measuring all its 2n possible configurations to determine their performances is usually infeasible. Thus, various techniques have been proposed to predict software performances based on a small sample of measured configurations. We propose a novel algorithm based on Fourier transform that is able to make predictions of any configurable software system with theoretical guarantees of accuracy and confidence level specified by the user, while using minimum number of samples up to a constant factor. Empirical results on the case studies constructed from real-world configurable systems demonstrate the effectiveness of our algorithm.
{"title":"Performance Prediction of Configurable Software Systems by Fourier Learning (T)","authors":"Yi Zhang, Jianmei Guo, Eric Blais, K. Czarnecki","doi":"10.1109/ASE.2015.15","DOIUrl":"https://doi.org/10.1109/ASE.2015.15","url":null,"abstract":"Understanding how performance varies across a large number of variants of a configurable software system is important for helping stakeholders to choose a desirable variant. Given a software system with n optional features, measuring all its 2n possible configurations to determine their performances is usually infeasible. Thus, various techniques have been proposed to predict software performances based on a small sample of measured configurations. We propose a novel algorithm based on Fourier transform that is able to make predictions of any configurable software system with theoretical guarantees of accuracy and confidence level specified by the user, while using minimum number of samples up to a constant factor. Empirical results on the case studies constructed from real-world configurable systems demonstrate the effectiveness of our algorithm.","PeriodicalId":6586,"journal":{"name":"2015 30th IEEE/ACM International Conference on Automated Software Engineering (ASE)","volume":"55 1","pages":"365-373"},"PeriodicalIF":0.0,"publicationDate":"2015-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86883181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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