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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 try_next(self):
 """Advance the cursor without blocking indefinitely. This method returns the next change document without waiting indefinitely for the next change. For example:: with db.collection.watch() as stream: while stream.alive: change = stream.try_next() if change is not None: print(change) elif stream.alive: # We end up here when there are no recent changes. # Sleep for a while to avoid flooding the server with # getMore requests when no changes are available. time.sleep(10) If no change document is cached locally then this method runs a single getMore command. If the getMore yields any documents, the next document is returned, otherwise, if the getMore returns no documents (because there have been no changes) then ``None`` is returned. :Returns: The next change document or ``None`` when no document is available after running a single getMore or when the cursor is closed. .. versionadded:: 3.8 """

        # Attempt to get the next change with at most one getMore and at most
        # one resume attempt.
        try:
            change = self._cursor._try_next(True)
        except ConnectionFailure:
            self._resume()
            change = self._cursor._try_next(False)
        except OperationFailure as exc:
            if exc.code in _NON_RESUMABLE_GETMORE_ERRORS:
                raise
            self._resume()
            change = self._cursor._try_next(False)

        # No changes are available.
        if change is None:
            return None

        try:
            resume_token = change['_id']
        except KeyError:
            self.close()
            raise InvalidOperation(
                "Cannot provide resume functionality when the resume "
                "token is missing.")
        self._resume_token = copy.copy(resume_token)
        self._start_at_operation_time = None

        if self._decode_custom:
            return _bson_to_dict(change.raw, self._orig_codec_options)
        return change