尝试在 Mac 上运行 scrapy crawl 时出现语法错误？ [复制]

Question

我按照 Scrapy.org 上的建议安装了 Scrapy，安装了 Xcode、自制软件，然后使用命令“pip3 install scrapy”。

在 pip 命令出现一些错误后，我还使用了“sudo easy_install pip”。

现在，每当我尝试运行我的 FirstSpider 时，我都会得到这个 SyntaxErrorscrapy crawl FirstSpider：

  File "/usr/local/lib/python3.7/site-packages/twisted/conch/manhole.py", line 154
    def write(self, data, async=False):
                              ^
SyntaxError: invalid syntax

谁能解释发生了什么或如何解决它？

完整的错误报告：

$ scrapy crawl FirstSpider
2018-08-30 23:14:58 [scrapy.utils.log] INFO: Scrapy 1.5.1 started (bot: Example)
2018-08-30 23:14:58 [scrapy.utils.log] INFO: Versions: lxml 4.2.4.0, libxml2 2.9.8, cssselect 1.0.3, parsel 1.5.0, w3lib 1.19.0, Twisted 18.7.0, Python 3.7.0 (default, Aug 22 2018, 15:22:33) - [Clang 9.1.0 (clang-902.0.39.2)], pyOpenSSL 18.0.0 (OpenSSL 1.1.0i  14 Aug 2018), cryptography 2.3.1, Platform Darwin-17.7.0-x86_64-i386-64bit
2018-08-30 23:14:58 [scrapy.crawler] INFO: Overridden settings: {'BOT_NAME': 'Example', 'NEWSPIDER_MODULE': 'Example.spiders', 'ROBOTSTXT_OBEY': True, 'SPIDER_MODULES': ['Example.spiders']}
Traceback (most recent call last):
  File "/usr/local/lib/scrapy", line 11, in <module>
    sys.exit(execute())
  File "/usr/local/lib/python3.7/site-packages/scrapy/cmdline.py", line 150, in execute
    _run_print_help(parser, _run_command, cmd, args, opts)
  File "/usr/local/lib/python3.7/site-packages/scrapy/cmdline.py", line 90, in _run_print_help
    func(*a, **kw)
  File "/usr/local/lib/python3.7/site-packages/scrapy/cmdline.py", line 157, in _run_command
    cmd.run(args, opts)
  File "/usr/local/lib/python3.7/site-packages/scrapy/commands/crawl.py", line 57, in run
    self.crawler_process.crawl(spname, **opts.spargs)
  File "/usr/local/lib/python3.7/site-packages/scrapy/crawler.py", line 170, in crawl
    crawler = self.create_crawler(crawler_or_spidercls)
  File "/usr/local/lib/python3.7/site-packages/scrapy/crawler.py", line 198, in create_crawler
    return self._create_crawler(crawler_or_spidercls)
  File "/usr/local/lib/python3.7/site-packages/scrapy/crawler.py", line 203, in _create_crawler
    return Crawler(spidercls, self.settings)
  File "/usr/local/lib/python3.7/site-packages/scrapy/crawler.py", line 55, in __init__
    self.extensions = ExtensionManager.from_crawler(self)
  File "/usr/local/lib/python3.7/site-packages/scrapy/middleware.py", line 58, in from_crawler
    return cls.from_settings(crawler.settings, crawler)
  File "/usr/local/lib/python3.7/site-packages/scrapy/middleware.py", line 34, in from_settings
    mwcls = load_object(clspath)
  File "/usr/local/lib/python3.7/site-packages/scrapy/utils/misc.py", line 44, in load_object
    mod = import_module(module)
  File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
  File "<frozen importlib._bootstrap>", line 983, in _find_and_load
  File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 728, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/usr/local/lib/python3.7/site-packages/scrapy/extensions/telnet.py", line 12, in <module>
    from twisted.conch import manhole, telnet
  File "/usr/local/lib/python3.7/site-packages/twisted/conch/manhole.py", line 154
    def write(self, data, async=False):
                              ^
SyntaxError: invalid syntax

Answer 1

您正在使用的代码需要针对您正在使用的较新的 Python 版本进行更新，如 async has become a reserved keyword in Python 3.7。

询问您正在使用的项目来解决此问题。同时，降级到 Python 3.6 可以让您运行该软件。

回溯显示错误出在twisted 项目中，该项目尚不支持 Python 3.7。该项目知道这一点并actively working towards fixing the problem。