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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 post_process(self, tagnum2name):
 """Map the tag name instead of tag number to the tag value. """

        for tag, value in self.raw_ifd.items():
            try:
                tag_name = tagnum2name[tag]
            except KeyError:
                # Ok, we don't recognize this tag.  Just use the numeric id.
                msg = 'Unrecognized Exif tag ({tag}).'.format(tag=tag)
                warnings.warn(msg, UserWarning)
                tag_name = tag
            self.processed_ifd[tag_name] = value