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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(self, value):
 """ Check if ``value`` is valid. :returns: [errors] If ``value`` is invalid, otherwise []. """

        errors = []

        # Make sure the type validates first.
        valid = self._is_valid(value)
        if not valid:
            errors.append(self.fail(value))
            return errors

        # Then validate all the constraints second.
        for constraint in self._constraints_inst:
            error = constraint.is_valid(value)
            if error:
                errors.append(error)

        return errors