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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 pull(self, repository, tag=None, stream=False, auth_config=None, decode=False, platform=None):
 """ Pulls an image. Similar to the ``docker pull`` command. Args: repository (str):
 The repository to pull tag (str):
 The tag to pull stream (bool):
 Stream the output as a generator. Make sure to consume the generator, otherwise pull might get cancelled. auth_config (dict):
 Override the credentials that are found in the config for this request. ``auth_config`` should contain the ``username`` and ``password`` keys to be valid. decode (bool):
 Decode the JSON data from the server into dicts. Only applies with ``stream=True`` platform (str):
 Platform in the format ``os[/arch[/variant]]`` Returns: (generator or str):
 The output Raises: :py:class:`docker.errors.APIError` If the server returns an error. Example: { "status": "Pulling image (latest) from busybox", "progressDetail": {}, "id": "e72ac664f4f0" } { "progressDetail": {}, "id": "e72ac664f4f0" } """

        if not tag:
            repository, tag = utils.parse_repository_tag(repository)
        registry, repo_name = auth.resolve_repository_name(repository)

        params = {
            'tag': tag,
            'fromImage': repository
        }
        headers = {}

        if auth_config is None:
            header = auth.get_config_header(self, registry)
            if header:
                headers['X-Registry-Auth'] = header
        else:
            log.debug('Sending supplied auth config')
            headers['X-Registry-Auth'] = auth.encode_header(auth_config)

        if platform is not None:
            if utils.version_lt(self._version, '1.32'):
                raise errors.InvalidVersion(
                    'platform was only introduced in API version 1.32'
                )
            params['platform'] = platform

        response = self._post(
            self._url('/images/create'), params=params, headers=headers,
            stream=stream, timeout=None
        )

        self._raise_for_status(response)

        if stream:
            return self._stream_helper(response, decode=decode)

        return self._result(response)