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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 to_raw(self, value, context=None):
 """Convert the value to a JSON compatible value"""

        if value is None:
            return None
        res = {}
        value = value.copy()
        errors = []
        for field in list(set(value) & set(self._fields)):
            schema = self._fields.get(field)
            name = schema.get_attr('name', field)
            try:
                res[name] = \
                    schema.to_raw(value.pop(field), context=context)
            except exceptions.ValidationErrors as ex:
                self._update_errors_by_exception(errors, ex, name)

        self._raise_exception_when_errors(errors, value)
        res.update(value)
        return res