How do I get rid of these messages?

How do I get rid of the messages like "NOTICE: CREATE TABLE / PRIMARY
KEY will create implicit index 'test_pkey' for table 'test'" coming out
from stderr when I run psql with my create table script?

(I don't want to direct them to /dev/null, since I still want to be able
to see the *real* sql error messages)

Thanks

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Wei Weng
Network Software Engineer
KenCast Inc.