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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 update_metadata(self, resource, keys_vals):
 """ Updates key-value pairs with the given resource. Will attempt to update all key-value pairs even if some fail. Keys must already exist. Args: resource (intern.resource.boss.BossResource) keys_vals (dictionary):
 Collection of key-value pairs to update on the given resource. Raises: HTTPErrorList on failure. """

        self.metadata_service.set_auth(self._token_metadata)
        self.metadata_service.update(resource, keys_vals)