What is "python-2.7"

Documentation for Python 2.7 can be found here.

For an explanation of why version 2.7 is the last of the 2.x series, read PEP 404.

Recommendation for the use of the tag:

Use the tag python for every Python-related issue. If you believe your question includes specific aspects and is incompatible with python-2.x or python-3.x use beyond the tag python, the tag python-2.x or the tag python-3.x. If it is a more specific case, use beyond the tag python another that specifies the language version, such as the tag python-2.7.