def __init__(
      self,
      custom_exchangers: Optional[
          Dict[str, Type[BaseAuthCredentialExchanger]]
      ] = None,
  ):
    """Initializes the AutoAuthCredentialExchanger.

    Args:
      custom_exchangers: Optional dictionary for adding or overriding auth
        exchangers. The key is the auth scheme, and the value is the credential
        exchanger class.
    """
    self.exchangers = {
        AuthCredentialTypes.OAUTH2: OAuth2CredentialExchanger,
        AuthCredentialTypes.OPEN_ID_CONNECT: OAuth2CredentialExchanger,
        AuthCredentialTypes.SERVICE_ACCOUNT: ServiceAccountCredentialExchanger,
    }

    if custom_exchangers:
      self.exchangers.update(custom_exchangers)
Initializes the AutoAuthCredentialExchanger.

    Args:
      custom_exchangers: Optional dictionary for adding or overriding auth
        exchangers. The key is the auth scheme, and the value is the credential
        exchanger class.
    
src/google/adk/tools/openapi_tool/auth/credential_exchangers/auto_auth_credential_exchanger.py