code: def get_signed_query_params_v2(credentials, expiration, string_to_sign):
      
      ensure_signed_credentials(credentials)
      signature_bytes = credentials.sign_bytes(string_to_sign)
      signature = base64.b64encode(signature_bytes)
      service_account_name = credentials.signer_email
      return {
          "GoogleAccessId": service_account_name,
          "Expires": str(expiration),
          "Signature": signature,
      }
docs: Gets query parameters for creating a signed URL.
  
      :type credentials: :class:`google.auth.credentials.Signing`
      :param credentials: The credentials used to create a private key
                          for signing text.
  
      :type expiration: int or long
      :param expiration: When the signed URL should expire.
  
      :type string_to_sign: str
      :param string_to_sign: The string to be signed by the credentials.
  
      :raises: :exc:`AttributeError` if credentials is not an instance
              of :class:`google.auth.credentials.Signing`.
  
      :rtype: dict
      :returns: Query parameters matching the signing credentials with a
                signed payload.