code: def from_p12_keyfile_buffer(cls, service_account_email, file_buffer,
                                  private_key_password=None, scopes='',
                                  token_uri=oauth2client.GOOGLE_TOKEN_URI,
                                  revoke_uri=oauth2client.GOOGLE_REVOKE_URI):
          
          private_key_pkcs12 = file_buffer.read()
          return cls._from_p12_keyfile_contents(
              service_account_email, private_key_pkcs12,
              private_key_password=private_key_password, scopes=scopes,
              token_uri=token_uri, revoke_uri=revoke_uri)
docs: Factory constructor from JSON keyfile.
  
          Args:
              service_account_email: string, The email associated with the
                                     service account.
              file_buffer: stream, A buffer that implements ``read()``
                           and contains the PKCS#12 key contents.
              private_key_password: string, (Optional) Password for PKCS#12
                                    private key. Defaults to ``notasecret``.
              scopes: List or string, (Optional) Scopes to use when acquiring an
                      access token.
              token_uri: string, URI for token endpoint. For convenience defaults
                         to Google's endpoints but any OAuth 2.0 provider can be
                         used.
              revoke_uri: string, URI for revoke endpoint. For convenience
                          defaults to Google's endpoints but any OAuth 2.0
                          provider can be used.
  
          Returns:
              ServiceAccountCredentials, a credentials object created from
              the keyfile.
  
          Raises:
              NotImplementedError if pyOpenSSL is not installed / not the
              active crypto library.