## 在学习爬虫中遇到很多坑，写出来供道友参考
- 出现诸如以下错误
ModuleNotFoundError: No module named 'js2xml'
NameError: name 'js2xml' is not defined
则可能是库没有导入
- 在将 str 转换为 json
JSONDecodeError: Extra data: line 1 column 234701 (char 234700)
则可能是 str 不符合 json 格式
1. 可以用 start 和 end 标示开头结尾，如 str[start, end] ；
2. 可以对 str 进行剪切，使用 strip('symbol') 方法，对首尾存在 symbol 的进行剪切
又或者是存在多重结构，则
One-liner for your problem:
data = [json.loads(line) for line in open('tweets.json', 'r')]。。。存坑
过去一段时间后，再次运行 jupyter notebook，出现错误
错误：
'jupyter' 不是内部或外部命令，也不是可运行的程序
原因及解决：环境变量中添加 D:\Users\23525\Anaconda3\Scripts，里面有 jupyter_notebook.exe、pip.exe 等命令
然后又出现如下错误：
Traceback (most recent call last):
File "C:\ProgramData\Anaconda3\Scripts\jupyter-notebook-script.py", line 6, in <module>
from notebook.notebookapp import main
File "C:\ProgramData\Anaconda3\lib\site-packages\notebook\notebookapp.py", line 47, in <module>
from zmq.eventloop import ioloop
File "C:\ProgramData\Anaconda3\lib\site-packages\zmq\__init__.py", line 47, in <module>
from zmq import backend
File "C:\ProgramData\Anaconda3\lib\site-packages\zmq\backend\__init__.py", line 40, in <module>
reraise(*exc_info)
File "C:\ProgramData\Anaconda3\lib\site-packages\zmq\utils\sixcerpt.py", line 34, in reraise
raise value
File "C:\ProgramData\Anaconda3\lib\site-packages\zmq\backend\__init__.py", line 27, in <module>
_ns = select_backend(first)
File "C:\ProgramData\Anaconda3\lib\site-packages\zmq\backend\select.py", line 27, in select_backend
mod = __import__(name, fromlist=public_api)
File "C:\ProgramData\Anaconda3\lib\site-packages\zmq\backend\cython\__init__.py", line 6, in <module>
from . import (constants, error, message, context,
ImportError: DLL load failed: 找不到指定的模块。
原因：问题都出现在 zmq 文件夹中，搜索答案需要重新安装 zmq
解决：
pip uninstall pyzmq pip install pyzmq 在 install 时又出现如下错误：
pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available. Collecting pyzmq
Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pyzmq/
Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pyzmq/
Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pyzmq/
Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pyzmq/
Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pyzmq/
Could not fetch URL https://pypi.org/simple/pyzmq/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/pyzmq/ (Caused by SSLError("Can't connect to HTTPS URL because the SSL module is not available.")) - skipping
Could not find a version that satisfies the requirement pyzmq (from versions: ) No matching distribution found for pyzmq pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available.
Could not fetch URL https://pypi.org/simple/pip/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/pip/ (Caused by SSLError("Can't connect to HTTPS URL because the SSL module is not available.")) - skipping
原因：
我得到了相同的“SSL模块不可用”错误运行Anaconda附带的原生点（目前为18.1）。在我的例子中，这是一个系统路径问题，我通过将以下目录添加到我的路径变量来解决：
%Miniconda3_DIR%;%Miniconda3_DIR%\Library\mingw-w64\bin;%Miniconda3_DIR%\Library\usr\bin;%Miniconda3_DIR%\Library\bin;%Miniconda3_DIR%\Scripts;%Miniconda3_DIR%\bin;在哪里，%Miniconda3_DIR%应该用你的Miniconda（或Anaconda）安装路径代替。
其实出现一段时间不能运行的程序，重新安装是最简单的操作，但我想要真正得解决问题，让我对世界能多少掌握一点控制权。通过一步步发现问题、解决问题、总结及预防，不正是人类发展的恒在规律吗？希望人类继承和探索之路长明。