A Python program to draw energy level diagram and to calculate quantum defects, the high lying Rydberg level

Rydberg atoms have strong and adjustable atomic interactions that can be tweaked by choosing different states with various principal quantum numbers or orbital angular momentum. They are highly used in quantum information applications. Furthermore, these atoms have long lifetimes and many possible energy levels, and their separations enable coupling to electromagnetic fields with frequencies ranging over six orders of magnitude. We studied some properties of these atoms and have developed a python program; the program gives two options. Firstly, it calculates energies of elements in s, p, d, and f orbitals and draws an energy level diagram of the element listed in the program. Secondly, it gives an option for calculating energy and quantum defects of atoms and ions, either listed or not listed in the program and generates their graphs accordingly. There are 21 elements in the database  whose energy level diagrams could be drawn. The database can be extended by adding more elements.