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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_uservars(self, user, data=None):
 """Set many variables for a user, or set many variables for many users. This function can be called in two ways:: # Set a dict of variables for a single user. rs.set_uservars(username, vars) # Set a nested dict of variables for many users. rs.set_uservars(many_vars) In the first syntax, ``vars`` is a simple dict of key/value string pairs. In the second syntax, ``many_vars`` is a structure like this:: { "username1": { "key": "value", }, "username2": { "key": "value", }, } This way you can export *all* user variables via ``get_uservars()`` and then re-import them all at once, instead of setting them once per user. :param optional str user: The user ID to set many variables for. Skip this parameter to set many variables for many users instead. :param dict data: The dictionary of key/value pairs for user variables, or else a dict of dicts mapping usernames to key/value pairs. This may raise a ``TypeError`` exception if you pass it invalid data types. Note that only the standard ``dict`` type is accepted, but not variants like ``OrderedDict``, so if you have a dict-like type you should cast it to ``dict`` first. """


        # Check the parameters to see how we're being used.
        if type(user) is dict and data is None:
            # Setting many variables for many users.
            for uid, uservars in user.items():
                if type(uservars) is not dict:
                    raise TypeError(
                        "In set_uservars(many_vars) syntax, the many_vars dict "
                        "must be in the format of `many_vars['username'] = "
                        "dict(key=value)`, but the contents of many_vars['{}']"
                        " is not a dict.".format(uid)
                    )

                self._session.set(uid, uservars)

        elif type(user) in [text_type, str] and type(data) is dict:
            # Setting variables for a single user.
            self._session.set(user, data)

        else:
            raise TypeError(
                "set_uservars() may only be called with types ({str}, dict) or "
                "(dict<{str}, dict>) but you called it with types ({a}, {b})"
                .format(
                    str="unicode" if sys.version_info[0] < 3 else "str",
                    a=type(user),
                    b=type(data),
                ),
            )