def get_requires_python(dist):
    # type: (pkg_resources.Distribution) -> Optional[str]
    """
    Return the "Requires-Python" metadata for a distribution, or None
    if not present.
    """
    pkg_info_dict = get_metadata(dist)
    requires_python = pkg_info_dict.get('Requires-Python')

    if requires_python is not None:
        # Convert to a str to satisfy the type checker, since requires_python
        # can be a Header object.
        requires_python = str(requires_python)

    return requires_python

    Return the "Requires-Python" metadata for a distribution, or None
    if not present.
    
product/gradle-plugin/src/main/python/pip/_internal/utils/packaging.py