Python 2.7 comes pre-installed on the current and recent releases (for the past five years) of macOS X. The pre-installed Apple-provided build can be found in the following folders on the Mac:

• /System/Library/Frameworks/Python.framework
• /usr/bin/python

However, you can install your own version from http://www.python.org/download/. The one caveat to this is that you will now have two installations of Python, and you have to be careful to make sure the paths and environments are cleanly separated.