>>> t= r'\xe6\x97\xa0\xe6\xb3\x95\xe5\x8a\xa0\xe8\xbd\xbd\xe6\x8e\xa7\xe5\x88\xb6\xe5\x99\xa8:Index.php'

>>> print (bytes(t).decode('utf-8'))
无法加载控制器:Index.php

>>> t= b'\xe6\x97\xa0\xe6\xb3\x95\xe5\x8a\xa0\xe8\xbd\xbd\xe6\x8e\xa7\xe5\x88\xb6\xe5\x99\xa8:Index.php'

>>> print (t.decode('utf-8'))
无法加载控制器:Index.php