How do I remove a substring from the end of a string in Python?

strip doesn't mean "remove this substring". x.strip(y) treats y as a set of characters and strips any characters in that set from both ends of x.

On Python 3.9 and newer you can use the removeprefix and removesuffix methods to remove an entire substring from either side of the string:

url = 'abcdc.com'
url.removesuffix('.com')    # Returns 'abcdc'
url.removeprefix('abcdc.')  # Returns 'com'

The relevant Python Enhancement Proposal is PEP-616.

On Python 3.8 and older you can use endswith and slicing:

url = 'abcdc.com'
if url.endswith('.com'):
    url = url[:-4]

Or a regular expression:

import re
url = 'abcdc.com'
url = re.sub('\.com$', '', url)

If you are sure that the string only appears at the end, then the simplest way would be to use 'replace':

url = 'abcdc.com'
print(url.replace('.com',''))

def strip_end(text, suffix):
    if suffix and text.endswith(suffix):
        return text[:-len(suffix)]
    return text