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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 convert_content(self, fpath: str) -> typing.Optional[dict]: """Convert content of source file with loader, provided with `loader_cls` self attribute. Returns dict with converted content if loader class support source file extenstions, otherwise return nothing."""

        try:
            loader = self.loader_cls(fpath)
        except UnsupportedExtensionError:
            return

        return loader.convert_content()