Regular expression for python syntax

Question

I want to write a python code generator, and it would be helpful if I had the regular expression that describes all valid python programs.

Does such a regular expression exist? What is it?

Answer 1

Such a regular expression cannot exist, because regular expressions are, by definition, not powerful enough to recognize Turing complete languages (such as python).

Answer 2

If you generate a string with fragment of a Python code, and you want to check whether it is syntactically correct, try the built-in function compile. It returns the resulting code object or it raises the SyntaxError exception.