Remove tags before restoring pickled ones (#329)
* Filter IgnoredForEqualityTag when unpickling * UNDO BEFORE MERGE: use pytools branch * add comment * Revert "UNDO BEFORE MERGE: use pytools branch" This reverts commit 5ad3f55e3ff787205d9928231a27b76630551f1f. * directly use pytato * don't modify node * simplify * clarify comment * simplify further