env - run a program in a modified environment, or print the environment
env [NAME=VALUE]... [command]
Options you will use
-i, --ignore-environment- Start with an empty environment.
-S, --split-string STRING- Split STRING into separate arguments; lets a #! line pass options: #!/usr/bin/env -S bash -e.
-u, --unset NAME- Remove NAME from the environment.
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