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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 is_discovered(self):
 """Return if target device is discovered."""

        if self.target_device is None:
            return False

        if None in (self.target_device.version_text, self.target_device.os_type, self.target_device.os_version,
                    self.target_device.inventory_text, self.target_device.family, self.target_device.platform):
            return False
        return True