code: def _set_req_to_reinstall(self, req):
          # type: (InstallRequirement) -> None
          
          # Don't uninstall the conflict if doing a user install and the
          # conflict is not a user install.
          if not self.use_user_site or dist_in_usersite(req.satisfied_by):
              req.conflicts_with = req.satisfied_by
          req.satisfied_by = None
docs: Set a requirement to be installed.