python实现递归加载目录下和子目录下所有指定类型文件

一个类中的代码片段，记录一下自己的递归实现，以备后查。

def loadingYamlFile(self, pathstr: str) -> str:
        oldcurpath = self.curpath
        if self.level == 0:
            self.curpath = self.targetpath
        else:
            self.curpath = self.curpath + "\\" + pathstr
        files = os.listdir(self.curpath)
        for f in files:
            if os.path.isdir(self.curpath + "\\" + f):
                if f[0] == ".":
                    pass
                else:
                    self.level = self.level + 1
                    self.curpath = self.loadingYamlFile(f)

            if os.path.isfile(self.curpath + "\\" + f) and "yaml" in f:
                filename = self.curpath + "\\" + f
                self.yamlfilelist.append(filename)
        return oldcurpath