vars.py 文件源码

def isidentifier(ident):
    """
    Determines, if string is valid Python identifier using the ast module.
    Orignally posted at: http://stackoverflow.com/a/29586366
    """

    if not isinstance(ident, string_types):
        return False

    try:
        root = ast.parse(ident)
    except SyntaxError:
        return False

    if not isinstance(root, ast.Module):
        return False

    if len(root.body) != 1:
        return False

    if not isinstance(root.body[0], ast.Expr):
        return False

    if not isinstance(root.body[0].value, ast.Name):
        return False

    if root.body[0].value.id != ident:
        return False

    return True