def unique_variable(pattern=None, ignore=None):
    if pattern is not None:
        if is_indvar(pattern.name):
            prefix = 'z'
        elif is_funcvar(pattern.name):
            prefix = 'F'
        elif is_eventvar(pattern.name):
            prefix = 'e0'
        else:
            assert False, "Cannot generate a unique constant"
    else:
        prefix = 'z'

    v = Variable("%s%s" % (prefix, _counter.get()))
    while ignore is not None and v in ignore:
        v = Variable("%s%s" % (prefix, _counter.get()))
    return v
JRPC test: services.leop.getPasses
dataset/ETHPy150Open nltk/nltk/nltk/sem/logic.py/unique_variable--crossover with--dataset/ETHPy150Open satnet-project/server/services/leop/tests/test_jrpc.py/TestLaunchViews.test_get_passes