def shell_out_ignore_exitcode(cmd, stderr=STDOUT, cwd=None):
try:<EOL><INDENT>return shell_out(cmd, stderr=stderr, cwd=cwd)<EOL><DEDENT>except CalledProcessError as c:<EOL><INDENT>return _clean_output(c.output)<EOL><DEDENT>
Same as shell_out but doesn't raise if the cmd exits badly.