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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 _get_non_empty_list(cls, iter):
 """Return a list of the input, excluding all ``None`` values."""

        res = []
        for value in iter:
            if hasattr(value, 'items'):
                value = cls._get_non_empty_dict(value) or None
            if value is not None:
                res.append(value)
        return res