code: def customer_id(self, customer_id):
          
  
          if customer_id is None:
              raise ValueError("Invalid value for `customer_id`, must not be `None`")
          if len(customer_id) > 50:
              raise ValueError("Invalid value for `customer_id`, length must be less than `50`")
  
          self._customer_id = customer_id
docs: Sets the customer_id of this ChargeRequest.
          The ID of the customer to associate this transaction with. This field is required if you provide a value for `customer_card_id`, and optional otherwise.
  
          :param customer_id: The customer_id of this ChargeRequest.
          :type: str