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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 _do_highlight(content, query, tag='em'):
 """ Highlight `query` terms in `content` with html `tag`. This method assumes that the input text (`content`) does not contain any special formatting. That is, it does not contain any html tags or similar markup that could be screwed up by the highlighting. Required arguments: `content` -- Content to search for instances of `text` `text` -- The text to be highlighted """

        for term in query:
            term = term.decode('utf-8')
            for match in re.findall('[^A-Z]+', term):  # Ignore field identifiers
                match_re = re.compile(match, re.I)
                content = match_re.sub('<%s>%s</%s>' % (tag, term, tag), content)

        return content