How to replace a substring in Python while keeping part of that string?

Question

Python

The essence of the question is this, you need in the input line like

string = "cos(90) + cos(170) + sin( 80)" #могут быть и другие математические функции

make these changes:

out_string = "cos(degres(90)) +  cos(degres(170)) + sin(degres( 80))"

I wrote such a regular expression:
(cos *\( *(?P<degres>[\d]+) *\))
how can I replace the cosines with it, and leave the numbers?
and another question: how to make it change both sines and tangents?

Answer 1

import re
string = "(cos(0) + sin(180)) * tan(45.0) + not_a_tan(1)"
print re.sub(r'\b(cos|sin|tan)\s*\(\s*(\d+(?:\.\d+)?)\s*\)', r'\1(degres(\2))', string)

Handles integer and fractional numbers correctly.
Does not respond to other functions ending in cos, sin, or tan.
At the same time corrects the spacing.