def _get_service_account_email(http_request=None):
    if http_request is None:
        http_request = httplib2.Http().request
    response, content = http_request(
        _DEFAULT_EMAIL_METADATA, headers={'Metadata-Flavor': 'Google'})
    if response.status == http_client.OK:
        content = _from_bytes(content)
        return None, content
    else:
        return response, content
Get the GCE service account email from the current environment.
dataset/ETHPy150Open google/oauth2client/oauth2client/contrib/gce.py/_get_service_account_email