postgres another version

1brew install postgres@9.6
2cp -rf /usr/local/Cellar/postgresql@9.6/9.6.9 /usr/local/Cellar/postgresql/.
3brew switch postgres 9.6.9
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1$ brew search postgresql
2==> Searching local taps...
3postgresql        postgresql@9.4        postgresql@9.5        postgresql@9.6
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