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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 _find_matcher(self, alias):
 """ Finds a matcher based on the given alias or raises an error if no matcher could be found. """

        matcher = lookup(alias)
        if not matcher:
            msg = 'Matcher "%s" not found' % alias

            # Try to find similarly named matchers to help the user
            similar = suggest(alias, max=3, cutoff=0.5)
            if len(similar) > 1:
                last = similar.pop()
                msg += '. Perhaps you meant to use %s or %s?' % (', '.join(similar), last)
            elif len(similar) > 0:
                msg += '. Perhaps you meant to use %s?' % similar.pop()

            raise KeyError(msg)

        return matcher