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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 to_bqstorage(self):
 """Construct a BigQuery Storage API representation of this table. Install the ``google-cloud-bigquery-storage`` package to use this feature. If the ``table_id`` contains a partition identifier (e.g. ``my_table$201812``) or a snapshot identifier (e.g. ``mytable@1234567890``), it is ignored. Use :class:`google.cloud.bigquery_storage_v1beta1.types.TableReadOptions` to filter rows by partition. Use :class:`google.cloud.bigquery_storage_v1beta1.types.TableModifiers` to select a specific snapshot to read from. Returns: google.cloud.bigquery_storage_v1beta1.types.TableReference: A reference to this table in the BigQuery Storage API. Raises: ValueError: If the :mod:`google.cloud.bigquery_storage_v1beta1` module cannot be imported. """

        if bigquery_storage_v1beta1 is None:
            raise ValueError(_NO_BQSTORAGE_ERROR)

        table_ref = bigquery_storage_v1beta1.types.TableReference()
        table_ref.project_id = self._project
        table_ref.dataset_id = self._dataset_id
        table_id = self._table_id

        if "@" in table_id:
            table_id = table_id.split("@")[0]

        if "$" in table_id:
            table_id = table_id.split("$")[0]

        table_ref.table_id = table_id

        return table_ref