code: def _requirements_sanitize(req_list):
      # type: (List[str]) -> List[str]
      
      filtered_req_list = (
          _requirement_find_lowest_possible(req) for req in
          (pkg_resources.Requirement.parse(s) for s in req_list)
          if _requirement_filter_by_marker(req)
      )
      return [" ".join(req) for req in filtered_req_list]
docs: Cleanup a list of requirement strings (e.g. from requirements.txt) to only
      contain entries valid for this platform and with the lowest required version
      only.
  
      Example
      -------
  
      >>> from sys import version_info
      >>> _requirements_sanitize([
      ...     'foo>=3.0',
      ...     "monotonic>=1.0,>0.1;python_version=='2.4'",
      ...     "bar>1.0;python_version=='{}.{}'".format(version_info[0], version_info[1])
      ... ])
      ['foo >= 3.0', 'bar > 1.0']