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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 coerce(self, value):
 """Convert from whatever is given to a list of scalars for the lookup_field."""

        if isinstance(value, dict):
            value = [value]
        if not isiterable_notstring(value):
            value = [value]
        return [coerce_single_instance(self.lookup_field, v) for v in value]