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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 inject(self, span_context, format, carrier):
 """Injects `span_context` into `carrier`. The type of `carrier` is determined by `format`. See the :class:`Format` class/namespace for the built-in OpenTracing formats. Implementations *must* raise :exc:`UnsupportedFormatException` if `format` is unknown or disallowed. :param span_context: the :class:`SpanContext` instance to inject :type span_context: SpanContext :param format: a python object instance that represents a given carrier format. `format` may be of any type, and `format` equality is defined by python ``==`` equality. :type format: Format :param carrier: the format-specific carrier object to inject into """

        if format in Tracer._supported_formats:
            return
        raise UnsupportedFormatException(format)