code: def forward(node, analysis):
    
    if not isinstance(analysis, Forward):
      raise TypeError('not a valid forward analysis object')
    for succ in gast.walk(node):
      if isinstance(succ, gast.FunctionDef):
        cfg_obj = CFG.build_cfg(succ)
        analysis.visit(cfg_obj.entry)
    return node
docs: Perform a given analysis on all functions within an AST.