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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 parse_stream(self, stream: BytesIO, context=None):
 """ Parse some python object from the stream. :param stream: Stream from which the data is read and parsed. :param context: Optional context dictionary. """

        if context is None:
            context = Context()
        if not isinstance(context, Context):
            context = Context(context)
        try:
            return self._parse_stream(stream, context)
        except Error:
            raise
        except Exception as exc:
            raise ParsingError(str(exc))