def ensure_inside_venv(ctx):
if not hasattr(sys, '<STR_LIT>'):<EOL><INDENT>echo_error("<STR_LIT>"<EOL>"<STR_LIT>"<EOL>"<STR_LIT>")<EOL>sys.exit(<NUM_LIT:2>)<EOL><DEDENT>
Display an error and exit if the program is not run from inside a
virtualenv.