pip错误：TypeError: parse() got an unexpected keyword argument 'transport_encoding'

Win10，ANACONDA3(64-bit)，Python3.6.2。ANACONDA Prompt中不能用pip命令安装包，并且是在安装了TensorFlow后才发生的。报错如下：

Exception:
Traceback (most recent call last):
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\basecommand.py", line 215, in main
    status = self.run(options, args)
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\commands\install.py", line 335, in run
    wb.build(autobuilding=True)
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\wheel.py", line 749, in build
    self.requirement_set.prepare_files(self.finder)
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\req\req_set.py", line 380, in prepare_files
    ignore_dependencies=self.ignore_dependencies))
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\req\req_set.py", line 554, in _prepare_file
    require_hashes
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\req\req_install.py", line 278, in populate_link
    self.link = finder.find_requirement(self, upgrade)
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\index.py", line 465, in find_requirement
    all_candidates = self.find_all_candidates(req.name)
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\index.py", line 423, in find_all_candidates
    for page in self._get_pages(url_locations, project_name):
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\index.py", line 568, in _get_pages
    page = self._get_page(location)
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\index.py", line 683, in _get_page
    return HTMLPage.get_page(link, session=self.session)
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\index.py", line 811, in get_page
    inst = cls(resp.content, resp.url, resp.headers)
  File "C:\ProgramData\Anaconda3\lib\site-packages\pip\index.py", line 731, in __init__
    namespaceHTMLElements=False,
TypeError: parse() got an unexpected keyword argument 'transport_encoding' 

解决办法：输入命令

conda install -c anaconda html5lib

会看到一系列更新的结果，然后再次使用pip安装包，发现可以成功安装

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更新

以上方法不成功的话，可以尝试输入命令：

conda install pip