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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, name, value):
 """Validate and return a value."""


        if self.valid_set and value not in self.valid_set:
            raise ImproperlyConfigured(
                "%s: \"%s\" is not a valid setting (choose between %s)." %
                (name, value, ", ".join("\"%s\"" % x for x in self.valid_set)))

        return value