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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_device_active(device):
 """ Checks dmsetup to see if a device is already active """

        cmd = ['dmsetup', 'info', device]
        dmsetup_info = util.subp(cmd)
        for dm_line in dmsetup_info.stdout.split("\n"):
            line = dm_line.split(':')
            if ('State' in line[0].strip()) and ('ACTIVE' in line[1].strip()):
                return True
        return False