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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 set_bucket_name(self, bucket_name):
 """ Set bucket name policy condition. :param bucket_name: set bucket name. """

        is_valid_bucket_name(bucket_name)

        self.policies.append(('eq', '$bucket', bucket_name))
        self.form_data['bucket'] = bucket_name
        self.bucket_name = bucket_name