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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 copy_blob( self, blob, destination_bucket, new_name=None, client=None, preserve_acl=True, source_generation=None, ):
 """Copy the given blob to the given bucket, optionally with a new name. If :attr:`user_project` is set, bills the API request to that project. :type blob: :class:`google.cloud.storage.blob.Blob` :param blob: The blob to be copied. :type destination_bucket: :class:`google.cloud.storage.bucket.Bucket` :param destination_bucket: The bucket into which the blob should be copied. :type new_name: str :param new_name: (optional) the new name for the copied file. :type client: :class:`~google.cloud.storage.client.Client` or ``NoneType`` :param client: Optional. The client to use. If not passed, falls back to the ``client`` stored on the current bucket. :type preserve_acl: bool :param preserve_acl: Optional. Copies ACL from old blob to new blob. Default: True. :type source_generation: long :param source_generation: Optional. The generation of the blob to be copied. :rtype: :class:`google.cloud.storage.blob.Blob` :returns: The new Blob. """

        client = self._require_client(client)
        query_params = {}

        if self.user_project is not None:
            query_params["userProject"] = self.user_project

        if source_generation is not None:
            query_params["sourceGeneration"] = source_generation

        if new_name is None:
            new_name = blob.name

        new_blob = Blob(bucket=destination_bucket, name=new_name)
        api_path = blob.path + "/copyTo" + new_blob.path
        copy_result = client._connection.api_request(
            method="POST",
            path=api_path,
            query_params=query_params,
            _target_object=new_blob,
        )

        if not preserve_acl:
            new_blob.acl.save(acl={}, client=client)

        new_blob._set_properties(copy_result)
        return new_blob