我在尝试通过这个GitHub项目学习股票预测。但是当我在cmd中运行存储库中提供的main.py文件时，遇到了一个错误
File "/Stock-Predictor/src/tweetstream/streamclasses.py", line 101 except urllib2.HTTPError, exception: ^SyntaxError: invalid syntax下面的代码是名为tweetstream的PyPi模块的一部分，即tweetstream/streamclasses.py。在Twitter情感分析项目中实现时出现了错误
import timeimport urllibimport urllib2import socketfrom platform import python_version_tupleimport anyjsonfrom . import AuthenticationError, ConnectionError, USER_AGENT class BaseStream(object): """A network connection to Twitters streaming API :param username: Twitter username for the account accessing the API. :param password: Twitter password for the account accessing the API. :keyword count: Number of tweets from the past to get before switching to live stream. :keyword url: Endpoint URL for the object. Note: you should not need to edit this. It's present to make testing easier. .. attribute:: connected True if the object is currently connected to the stream. .. attribute:: url The URL to which the object is connected .. attribute:: starttime The timestamp, in seconds since the epoch, the object connected to the streaming api. .. attribute:: count The number of tweets that have been returned by the object. .. attribute:: rate The rate at which tweets have been returned from the object as a float. see also :attr: `rate_period`. .. attribute:: rate_period The amount of time to sample tweets to calculate tweet rate. By default 10 seconds. Changes to this attribute will not be reflected until the next time the rate is calculated. The rate of tweets vary with time of day etc. so it's useful to set this to something sensible. .. attribute:: user_agent User agent string that will be included in the request. NOTE: This can not be changed after the connection has been made. This property must thus be set before accessing the iterator. The default is set in :attr: `USER_AGENT`. """ def __init__(self, username, password, catchup=None, url=None): self._conn = None self._rate_ts = None self._rate_cnt = 0 self._username = username self._password = password self._catchup_count = catchup self._iter = self.__iter__() self.rate_period = 10 # in seconds self.connected = False self.starttime = None self.count = 0 self.rate = 0 self.user_agent = USER_AGENT if url: self.url = url def __enter__(self): return self def __exit__(self, *params): self.close() return False def _init_conn(self): """Open the connection to the twitter server""" headers = {'User-Agent': self.user_agent} postdata = self._get_post_data() or {} if self._catchup_count: postdata["count"] = self._catchup_count poststring = urllib.urlencode(postdata) if postdata else None req = urllib2.Request(self.url, poststring, headers) password_mgr = urllib2.HTTPPasswordMgrWithDefaultRealm() password_mgr.add_password(None, self.url, self._username, self._password) handler = urllib2.HTTPBasicAuthHandler(password_mgr) opener = urllib2.build_opener(handler) try: self._conn = opener.open(req) except urllib2.HTTPError, exception: #___________________________problem here if exception.code == 401: raise AuthenticationError("Access denied") elif exception.code == 404: raise ConnectionError("URL not found: %s" % self.url) else: # re raise. No idea what would cause this, so want to know raise except urllib2.URLError, exception: raise ConnectionError(exception.reason)回答：
except块中的第二个项目是用于访问异常信息的标识符。try/except语法在Python 2和Python 3之间发生了变化，您的代码是Python 2的语法。
Python 2（语言参考）：
try: ...except <expression>, <identifier>: ...try: ...except <expression> as <identifier>: ...请注意，这可以是一个单一的异常类，也可以是一个异常类的元组，用于在一个except子句中捕获多种类型的异常，因此为了回答您标题中的问题，您可以使用以下方法来处理可能抛出的多个异常：
try: x = array[5] # 如果array不存在则引发NameError，如果索引过大则引发IndexErrorexcept (IndexError,NameError) as e: print(e) # 这是哪种错误？