code: def client_certificate(self, client_certificate):
          
          if client_certificate is None:
              raise ValueError("Invalid value for `client_certificate`, must not be `None`")
          if client_certificate is not None and len(client_certificate) > 3000:
              raise ValueError("Invalid value for `client_certificate`, length must be less than or equal to `3000`")
  
          self._client_certificate = client_certificate
docs: Sets the client_certificate of this GlobalSignCredentials.
          The client certificate provided by GlobalSign to allow HTTPS connection over TLS/SSL. The certificate wraps a public key that matches a private key provided by the customer. The certificate must be in PEM format. 
  
          :param client_certificate: The client_certificate of this GlobalSignCredentials.
          :type: str