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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 error(self):
 """Return user-friendly error message."""

        try:
            errcode = DeviceErrorCode(self.error_code)
            return "%s (%s): %s" % (errcode.name, errcode.value, self.error_message)
        except:
            return "Error %s: %s" % (self.error_code, self.error_message)