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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 _validate_iterable(self, is_iterable, key, value):
 """Validate fields with `iterable` key in schema set to True"""

        if is_iterable:
            try:
                iter(value)
            except TypeError:
                self._error(key, "Must be iterable (e.g. a list or array)")