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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 _make_class(cls, **kwargs):
 """Return a custom Visual class with given parameters."""

    kwargs = {k: (v if v is not None else getattr(cls, k, None))
              for k, v in kwargs.items()}
    # The class name contains a hash of the custom parameters.
    name = cls.__name__ + '_' + _hash(kwargs)
    if name not in _CLASSES:
        logger.log(5, "Create class %s %s.", name, kwargs)
        cls = type(name, (cls,), kwargs)
        _CLASSES[name] = cls
    return _CLASSES[name]