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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 convert_field(self, value, conversion):
 """When field missing, store conversion specifier."""

        if isinstance(value, MissingField):
            if conversion is not None:
                value.conversion = conversion
            return value

        return super(FormatterWrapper, self).convert_field(value, conversion)