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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 transform(self, pyobject):
 """Transform a `PyObject` to textual form"""

        if pyobject is None:
            return ('none',)
        object_type = type(pyobject)
        try:
            method = getattr(self, object_type.__name__ + '_to_textual')
            return method(pyobject)
        except AttributeError:
            return ('unknown',)