docs: def value(self):
          """Retrieve the data value of this attachment.
  
          Will show the filename of the attachment if there is an attachment available otherwise None
          Use save_as in order to download as a file.
  
          Example
          -------
  
          >>> file_attachment_property = project.part('Bike').property('file_attachment')
          >>> if file_attachment_property.value:
          ...     file_attachment_property.save_as('file.ext')
          ... else:
          ...     print('file attachment not set, its value is None')
  
          """
          if 'value' in self._json_data and self._json_data['value']:
              return "[Attachment: {}]".format(self._json_data['value'].split('/')[-1])
          else:
              return None