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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 get_service_account_email(self, project=None):
 """Get the email address of the project's BigQuery service account Note: This is the service account that BigQuery uses to manage tables encrypted by a key in KMS. Args: project (str, optional):
 Project ID to use for retreiving service account email. Defaults to the client's project. Returns: str: service account email address Example: my_service_account@my-project.iam.gserviceaccount.com """

        if project is None:
            project = self.project
        path = "/projects/%s/serviceAccount" % (project,)
        api_response = self._connection.api_request(method="GET", path=path)
        return api_response["email"]