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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 from_json(self, filename: str, silent: bool=False) -> None: """Load the configuration values from a JSON formatted file. This allows configuration to be loaded as so .. code-block:: python app.config.from_json('config.json') Arguments: filename: The filename which when appended to :attr:`root_path` gives the path to the file. silent: If True any errors will fail silently. """

        file_path = self.root_path / filename
        try:
            with open(file_path) as file_:
                data = json.loads(file_.read())
        except (FileNotFoundError, IsADirectoryError):
            if not silent:
                raise
        else:
            self.from_mapping(data)