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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def layout_json(self):
 """Return layout.json contents."""

        file_fqpn = os.path.join(self.app_path, 'layout.json')
        if self._layout_json is None:
            if os.path.isfile(file_fqpn):
                try:
                    with open(file_fqpn, 'r') as fh:
                        self._layout_json = json.load(fh)
                except ValueError as e:
                    self.handle_error('Failed to load "{}" file ({}).'.format(file_fqpn, e))
            else:
                self.handle_error('File "{}" could not be found.'.format(file_fqpn))
        return self._layout_json