parameters: (f)
return_statement: return keep
docstring: Negate a filter.
  
    Args:
      f: filter function to invert
  
    Returns:
      A filter function that returns the negation of f.
docstring_summary: Negate a filter.
docstring_tokens: Negate a filter .
function: def negation(f):
    """Negate a filter.
  
    Args:
      f: filter function to invert
  
    Returns:
      A filter function that returns the negation of f.
    """
    def keep(paths):
      l = set(paths)
      r = set(f(paths))
      return sorted(list(l-r))
    return keep
function_tokens: def negation ( f ) : def keep ( paths ) : l = set ( paths ) r = set ( f ( paths ) ) return sorted ( list ( l - r ) ) return keep