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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(format):
 """ Find and return a serializer for the given format. Arguments: format -- A Format instance. """

    try:
        serializer = SERIALIZERS[format]
    except KeyError:
        raise UnknownSerializer('No serializer found for %s' % format.acronym)

    return serializer