def loads(self, requirements_text):
        lines = re.findall(Requirement.spec_regex,
                           requirements_text,
                           re.MULTILINE)
        for line in lines:
            self.add(Requirement(line[0], "".join(line[1:])))
def _swdb_environment_upgrade(self, env_id, pkg_types, groups):
        if not self._base.history.env.get(env_id):
            self._raise_or_warn(self._ignore_installed,_("Environment id '%s' is not installed.") % env_id)
            return

        swdb_env = self._create_swdb_environment(env_id, pkg_types, groups)

        if swdb_env is not None:
            self._base.history.env.upgrade(swdb_env)