def env(*_vars, **kwargs):
for v in _vars:<EOL><INDENT>value = os.environ.get(v, None)<EOL>if value:<EOL><INDENT>return value<EOL><DEDENT><DEDENT>return kwargs.get('<STR_LIT:default>', '<STR_LIT>')<EOL>
Search for the first defined of possibly many env vars.

    Returns the first environment variable defined in vars, or
    returns the default defined in kwargs.