message: fixes AttributeError: 'module' object has no attribute 'exist'
diff: @@ -403,7 +403,7 @@ def build_distribution(release_tag, release_version, c_driver_dir, quiet):
  outs, errs = proc.communicate()
  dist_file = 'mongo-cxx-driver-{}.tar.gz'.format(release_tag)
  - if proc.returncode == 0 and os.path.exist(dist_file):
  + if proc.returncode == 0 and os.path.exists(dist_file):
  if not quiet:
  click.echo('C++ Driver build was successful.')
  click.echo('Distribution file: {}'.format(dist_file))
  