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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 bucket(self, bucket_name, user_project=None):
 """Factory constructor for bucket object. .. note:: This will not make an HTTP request; it simply instantiates a bucket object owned by this client. :type bucket_name: str :param bucket_name: The name of the bucket to be instantiated. :type user_project: str :param user_project: (Optional) the project ID to be billed for API requests made via the bucket. :rtype: :class:`google.cloud.storage.bucket.Bucket` :returns: The bucket object created. """

        return Bucket(client=self, name=bucket_name, user_project=user_project)