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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 create_identity_matcher(matcher='default', blacklist=None, sources=None, strict=True):
 """Create an identity matcher of the given type. Factory function that creates an identity matcher object of the type defined on 'matcher' parameter. A blacklist can also be added to ignore those values while matching. :param matcher: type of the matcher :param blacklist: list of entries to ignore while matching :param sources: only match the identities from these sources :param strict: strict matching (i.e, well-formed email addresses) :returns: a identity matcher object of the given type :raises MatcherNotSupportedError: when the given matcher type is not supported or available """

    import sortinghat.matching as matching

    if matcher not in matching.SORTINGHAT_IDENTITIES_MATCHERS:
        raise MatcherNotSupportedError(matcher=str(matcher))

    klass = matching.SORTINGHAT_IDENTITIES_MATCHERS[matcher]

    return klass(blacklist=blacklist, sources=sources, strict=strict)