def _prepare(
    install_requires: _StrOrIter, extras_require: Mapping[str, _StrOrIter]
) -> Tuple[List[str], Dict[str, List[str]]]:
    """Given values for ``install_requires`` and ``extras_require``
    create modified versions in a way that can be written in ``requires.txt``
    """
    extras = _convert_extras_requirements(extras_require)
    return _move_install_requirements_markers(install_requires, extras)
Given values for ``install_requires`` and ``extras_require``
    create modified versions in a way that can be written in ``requires.txt``
    
product/gradle-plugin/src/main/python/setuptools/command/_requirestxt.py