python 3.8安装第三方包（pip install）报 unicodedecodeerror错误，请教！

【一】环境
我的python环境是anacoda1.10，python 3.8。安装在windows server 2008 R2服务器上。
【二】故障
在使用pip install -r 命令安装本地包时，先报错：
UnicodeDecodeError: 'gbk' codec can't decode byte 0xda in position 18: illegal multibyte sequence
网上百度，将系统变量PYTHONUTF值设为1，重启，不同内容的报错：
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xf5 in position 15: invalid start byte
2次报错都指向同一个文件：encoding.py。

#第一次 
C:\Users\Administrator>pip install -r F:\mypython\package\PyMySQL-1.0.2-py3-none-any.whl
ERROR: Exception:
Traceback (most recent call last):
  File "e:\Anaconda3\lib\site-packages\pip\_internal\cli\base_command.py", line228, in _main    status = self.run(options, args)
  File "e:\Anaconda3\lib\site-packages\pip\_internal\cli\req_command.py", line 182, in wrapper    return func(self, options, args)
  File "e:\Anaconda3\lib\site-packages\pip\_internal\commands\install.py", line294, in run
    reqs = self.get_requirements(args, options, finder, session)
  File "e:\Anaconda3\lib\site-packages\pip\_internal\cli\req_command.py", line 334, in get_requirements
    for parsed_req in parse_requirements(
  File "e:\Anaconda3\lib\site-packages\pip\_internal\req\req_file.py", line 150, in parse_requirements
    for parsed_line in parser.parse(filename, constraint):
  File "e:\Anaconda3\lib\site-packages\pip\_internal\req\req_file.py", line 338, in parse
    for line in self._parse_and_recurse(filename, constraint):
  File "e:\Anaconda3\lib\site-packages\pip\_internal\req\req_file.py", line 343, in _parse_and_recurse
    for line in self._parse_file(filename, constraint):
  File "e:\Anaconda3\lib\site-packages\pip\_internal\req\req_file.py", line 376, in _parse_file_, content = get_file_content(
  File "e:\Anaconda3\lib\site-packages\pip\_internal\req\req_file.py", line 584, in get_file_content    content = auto_decode(f.read())
  File "e:\Anaconda3\lib\site-packages\pip\_internal\utils\encoding.py", line 39, in auto_decode
    return data.decode(
UnicodeDecodeError: 'gbk' codec can't decode byte 0xda in position 18: illegal multibyte sequence

#第二次
C:\Users\Administrator>pip install -r F:\mypython\package\PyMySQL-1.0.2-py3-none-any.whl
ERROR: Exception:
Traceback (most recent call last):
  File "e:\Anaconda3\lib\site-packages\pip\_internal\cli\base_command.py", line 228, in _main    status = self.run(options, args)
  File "e:\Anaconda3\lib\site-packages\pip\_internal\cli\req_command.py", line 182, in wrapper     return func(self, options, args)
  File "e:\Anaconda3\lib\site-packages\pip\_internal\commands\install.py", line294, in run  reqs = self.get_requirements(args, options, finder, session)
  File "e:\Anaconda3\lib\site-packages\pip\_internal\cli\req_command.py", line 334, in get_requirements
    for parsed_req in parse_requirements(
  File "e:\Anaconda3\lib\site-packages\pip\_internal\req\req_file.py", line 150, in parse_requirements    for parsed_line in parser.parse(filename, constraint):
  File "e:\Anaconda3\lib\site-packages\pip\_internal\req\req_file.py", line 338, in parse
    for line in self._parse_and_recurse(filename, constraint):
  File "e:\Anaconda3\lib\site-packages\pip\_internal\req\req_file.py", line 343, in _parse_and_recurse
    for line in self._parse_file(filename, constraint):
  File "e:\Anaconda3\lib\site-packages\pip\_internal\req\req_file.py", line 376, in _parse_file_, content = get_file_content(
  File "e:\Anaconda3\lib\site-packages\pip\_internal\req\req_file.py", line 584, in get_file_content    content = auto_decode(f.read())
  File "e:\Anaconda3\lib\site-packages\pip\_internal\utils\encoding.py", line 39, in auto_decode
    return data.decode(
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xf5 in position 15: invalid start byte