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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 import_classes(names, src, dst):
 """Import classes in package from their implementation modules."""

    for name in names:
        module = importlib.import_module('pygsp.' + src + '.' + name.lower())
        setattr(sys.modules['pygsp.' + dst], name, getattr(module, name))