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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 _update_field(self, action, field, value, max_tries, tries=0):
 """ Private update_field method. Wrapped by Document.update_field. Tracks a "tries" var to help limit recursion. """

        # Refresh our view of the document.
        self.fetch()

        # Update the field.
        action(self, field, value)

        # Attempt to save, retrying conflicts up to max_tries.
        try:
            self.save()
        except requests.HTTPError as ex:
            if tries < max_tries and ex.response.status_code == 409:
                self._update_field(
                    action, field, value, max_tries, tries=tries+1)
            else:
                raise