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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 dump(cls, filename, objects, properties, bools, encoding):
 """Write serialized objects, properties, bools to file."""

        if encoding is None:
            encoding = cls.encoding

        source = cls.dumps(objects, properties, bools)
        if PY2:
            source = unicode(source)

        with io.open(filename, 'w', encoding=encoding) as fd:
            fd.write(source)