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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, messages=None):
 """Returns True if the given Argument value is valid, False otherwise. Validation error messages are appended to an optional messages array. """

        valid     = True
        primitive = value

        def log(msg):
            if messages is not None:
                messages.append(msg)

        if self.enum:
            if value not in self.enum.keys():
                valid = False
                args  = (self.name, str(value))
                log("%s value '%s' not in allowed enumerated values." % args)
            else:
                primitive = int(self.enum[value])

        if self.type:
            if self.type.validate(primitive, messages, self.name) is False:
                valid = False

        if self.range:
            if primitive < self.range[0] or primitive > self.range[1]:
                valid = False
                args  = (self.name, str(primitive), self.range[0], self.range[1])
                log("%s value '%s' out of range [%d, %d]." % args)

        return valid