  Two-way quantum computers (2WQC) are proposed extension of standard 1WQC:
adding conjugated state preparation operation $\langle 0|$ similar to
postselection $|0\ra \langle 0|$, by performing a process which from
perspective of CPT symmetry is the original state preparation process, for
example by reversing EM impulses used for state preparation. As there were
concerns that this extension might violate no-cloning theorem for example for
attacks on quantum cryptographic protocols like BB84, here we extend the
original proof to show this theorem still holds for 2WQC and postselection.
