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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, transform, desc=None):
 """ Create a copy of this query, transformed by `transform`. Args: transform (callable):
 Callable that takes an iterable of values and returns an iterable of transformed values. Keyword Args: desc (str):
 A description of the transform, to use in log messages. Defaults to the name of the `transform` function. Returns: Query """

        if desc is None:
            desc = u'transform({})'.format(getattr(transform, '__name__', ''))

        return self.replace(
            transforms=self.transforms + [transform],
            desc_stack=self.desc_stack + [desc]
        )