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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 login(self, username, password, limit=10, sync=True, device_id=None):
 """Login to the homeserver. Args: username (str):
 Account username password (str):
 Account password limit (int):
 Deprecated. How many messages to return when syncing. This will be replaced by a filter API in a later release. sync (bool):
 Optional. Whether to initiate a /sync request after logging in. device_id (str):
 Optional. ID of the client device. The server will auto-generate a device_id if this is not specified. Returns: str: Access token Raises: MatrixRequestError """

        response = self.api.login(
            "m.login.password", user=username, password=password, device_id=device_id
        )
        self.user_id = response["user_id"]
        self.token = response["access_token"]
        self.hs = response["home_server"]
        self.api.token = self.token
        self.device_id = response["device_id"]

        if self._encryption:
            self.olm_device = OlmDevice(
                self.api, self.user_id, self.device_id, **self.encryption_conf)
            self.olm_device.upload_identity_keys()
            self.olm_device.upload_one_time_keys()

        if sync:
            """ Limit Filter """
            self.sync_filter = '{ "room": { "timeline" : { "limit" : %i } } }' % limit
            self._sync()
        return self.token