code: def each_item(*validators):
      
      def validate(value):
          for item in value:
              for validator in validators:
                  error = validator(item)
                  if error:
                      return error
          return None
      return validate
docs: A wrapper which applies the given validators to each item in a field
      value of type `list`.
  
      Example usage in a Schema:
  
      "my_list_field": {"type": Array(int), "validates": each_item(lte(10))}