解决系统不同Python版本下，repo因不同版本导致的SyntaxError: invalid syntax异常

Posted 2022-06-29 高桐@BILL

首先，repo同步代码时报错，如下：

repo init -u https://android.googlesource.com/platform/manifest -b android-10.0.0_r40
  File "/mnt/f/13_car/QQ3A.200705.002/.repo/repo/main.py", line 79
    file=sys.stderr)
        ^
SyntaxError: invalid syntax

if sys.version_info.major < 3:
  print('repo: error: Python 2 is no longer supported; '
        'Please upgrade to Python .+.'.format(*MIN_PYTHON_VERSION_SOFT),
        file=sys.stderr)
  sys.exit(1)
else:
  if sys.version_info < MIN_PYTHON_VERSION_HARD:
    print('repo: error: Python 3 version is too old; '
          'Please upgrade to Python .+.'.format(*MIN_PYTHON_VERSION_SOFT),
          file=sys.stderr)
    sys.exit(1)
  elif sys.version_info < MIN_PYTHON_VERSION_SOFT:
    print('repo: warning: your Python 3 version is no longer supported; '
          'Please upgrade to Python .+.'.format(*MIN_PYTHON_VERSION_SOFT),
          file=sys.stderr)

那么确认为是python版本问题，则卸载掉python2.7等无关版本，接着重新同步代码时发现repo不见了，查看日志发现卸载到python2.7时，repo被一起卸载了，日志如下：

root@HuangYaBin1:/mnt/f/13_car/QQ3A.200705.002# apt-get remove python2.7
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  libice-dev libpthread-stubs0-dev libpython-stdlib libpython2.7-minimal libpython2.7-stdlib libsm-dev libx11-dev
  libx11-doc libxau-dev libxcb1-dev libxdmcp-dev libxt-dev openjdk-9-jdk-headless python-minimal python2.7-minimal
  x11proto-core-dev x11proto-input-dev x11proto-kb-dev xorg-sgml-doctools xtrans-dev
Use 'apt autoremove' to remove them.
The following packages will be REMOVED:
  python python-kerberos python2.7 repo

则没办法重新安装repo，又发现repo安装时会自动安装python2.7并配置python环境变量；

如下为部分安装日志：

Unpacking python-kerberos (1.1.5-2build1) ...
Selecting previously unselected package repo.
Preparing to unpack .../repo_1.12.32-2_all.deb ...
Unpacking repo (1.12.32-2) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up python2.7 (2.7.12-1ubuntu0~16.04.18) ...
Setting up python (2.7.12-1~16.04) ...
Setting up python-kerberos (1.1.5-2build1) ...
Setting up repo (1.12.32-2) ...

那么没办法设置python别名，默认执行python是使用python3.8，命令如下：

alias /usr/bin/python3.8 /usr/bin/python

虽然执行python的时候，使用的是默认python3.8但实际上执行repo init时依然报同样的错。

最终建立一个软链接解决问题；

ln -s /usr/bin/python3.8 /usr/bin/python.