Merge pull request #1274 from wimglenn/Requires-Python

A better description for "Requires-Python" metadata field

Author: chrysle

source/specifications/core-metadata.rst

@@ -551,18 +551,17 @@ Requires-Python
 .. versionadded:: 1.2
 
 This field specifies the Python version(s) that the distribution is
-guaranteed to be compatible with. Installation tools may look at this when
+compatible with. Installation tools may look at this when
 picking which version of a project to install.
 
 The value must be in the format specified in :doc:`version-specifiers`.
 
-This field cannot be followed by an environment marker.
+For example, if a distribution uses :ref:`f-strings <whatsnew36-pep498>`
+then it may prevent installation on Python < 3.6 by specifying::
 
-Examples::
+    Requires-Python: >=3.6
 
-    Requires-Python: >=3
-    Requires-Python: >2.6,!=3.0.*,!=3.1.*
-    Requires-Python: ~=2.6
+This field cannot be followed by an environment marker.
 
 .. _core-metadata-requires-external: