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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 exists(device=''):
    '''
    Check to see if the partition exists

    CLI Example:

    .. code-block:: bash

        salt '*' partition.exists /dev/sdb1
    '''
    if os.path.exists(device):
        dev = os.stat(device).st_mode

        if stat.S_ISBLK(dev):
            return True

    return False