Env prints Go environment information.
By default env prints information as a shell script (on Windows, a batch file). If one or more variable
names is given as arguments, env prints the value of each named variable on its own line.
-json prints the environment in JSON format instead of as a shell script.
-u requires one or more arguments and unsets the default setting for the named environment variables,
if one has been set with ‘go env -w’.
-w requires one or more arguments of the form NAME=VALUE and changes the default settings of the
named environment variables to the given values.
For more about environment variables, see ‘go help environment’.