def scopes_to_string(scopes):
  """Converts scope value to a string.

  If scopes is a string then it is simply passed through. If scopes is an
  iterable then a string is returned that is all the individual scopes
  concatenated with spaces.

  Args:
    scopes: string or iterable of strings, the scopes.

  Returns:
    The scopes formatted as a single string.
  """
  if isinstance(scopes, str):
    return scopes
  else:
    return ' '.join(scopes)