question：　　tar: Error opening archive: Failed to open ‘/Users/……

answer:
As shown in the picture, if you get an error when installing the six dependency, then install the six dependency package separately, brew install six.

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question:
.Logging to ‘/usr/local/var/mysql/leodeMacBook-Pro.local.err’.
ERROR! The server quit without updating PID file (/usr/local/var/mysql/leodeMacBook-Pro.local.pid).