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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 list_datasets( self, project=None, include_all=False, filter=None, max_results=None, page_token=None, retry=DEFAULT_RETRY, ):
 """List datasets for the project associated with this client. See https://cloud.google.com/bigquery/docs/reference/rest/v2/datasets/list Args: project (str):
 Optional. Project ID to use for retreiving datasets. Defaults to the client's project. include_all (bool):
 Optional. True if results include hidden datasets. Defaults to False. filter (str):
 Optional. An expression for filtering the results by label. For syntax, see https://cloud.google.com/bigquery/docs/reference/rest/v2/datasets/list#filter. max_results (int):
 Optional. Maximum number of datasets to return. page_token (str):
 Optional. Token representing a cursor into the datasets. If not passed, the API will return the first page of datasets. The token marks the beginning of the iterator to be returned and the value of the ``page_token`` can be accessed at ``next_page_token`` of the :class:`~google.api_core.page_iterator.HTTPIterator`. retry (google.api_core.retry.Retry):
 Optional. How to retry the RPC. Returns: google.api_core.page_iterator.Iterator: Iterator of :class:`~google.cloud.bigquery.dataset.DatasetListItem`. associated with the project. """

        extra_params = {}
        if project is None:
            project = self.project
        if include_all:
            extra_params["all"] = True
        if filter:
            # TODO: consider supporting a dict of label -> value for filter,
            # and converting it into a string here.
            extra_params["filter"] = filter
        path = "/projects/%s/datasets" % (project,)
        return page_iterator.HTTPIterator(
            client=self,
            api_request=functools.partial(self._call_api, retry),
            path=path,
            item_to_value=_item_to_dataset,
            items_key="datasets",
            page_token=page_token,
            max_results=max_results,
            extra_params=extra_params,
        )