calculator program in Python with the following characteristics:

1. It must be at least 50 lines of code excluding comments
2. It must have the following functions:+,-,*,/, SQRT, and work with decimal numbers.
3. It must be all text, no high resolution graphics
4. It must automatically copy the result to the operating system clipboard
5. It must work as a functional calculator (calculations can be entered over and over)

Solutions that require the user install any softwarewill NOT be accepted (in case you are not sure, this means NO Pyperclip.)