code: def check_requirements(dist, attr, value):
      
      try:
          list(pkg_resources.parse_requirements(value))
      except (TypeError,ValueError):
          raise DistutilsSetupError(
              "%r must be a string or list of strings "
              "containing valid project/version requirement specifiers" % (attr,)
          )
docs: Verify that install_requires is a valid requirements list