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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 write_or_delete_file(self, what, filename, data, force=False):
 """Write `data` to `filename` or delete if empty If `data` is non-empty, this routine is the same as ``write_file()``. If `data` is empty but not ``None``, this is the same as calling ``delete_file(filename)`. If `data` is ``None``, then this is a no-op unless `filename` exists, in which case a warning is issued about the orphaned file (if `force` is false), or deleted (if `force` is true). """

        if data:
            self.write_file(what, filename, data)
        elif os.path.exists(filename):
            if data is None and not force:
                log.warn(
                    "%s not set in setup(), but %s exists", what, filename
                )
                return
            else:
                self.delete_file(filename)