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Some operations on MAC need system permission. When you enter the correct password, you can set the command: sudo Chmod – R 777 needs to modify the path of the upper directory of the file

However, except in some cases, such as moving sudo to the/usr/bin directory or sudo PIP update, it will still fail and prompt operation not permitted

Reason: SIP (system integrity protection) is enabled in MAC, and rootless mechanism is added. As a result, the file cannot be modified even under the root permission, so the protection mechanism can only be modified after it is closed

1) Restart the computer. When the apple logo appears on the screen, follow Command + R until you enter the protection mode

2) Protection mode: a dialog box in the middle of the screen prompts to restore a backup, or restore the factory system, etc. There is a row of toolbars in the upper left corner

3) Find the terminal terminal in the upper left corner, open it, and enter csrutil disable

4) Restart the computer again to modify the files in the usr/bin directory

PS: if you want to restore the protection mechanism and re-enter the protection mode, enter csrutil enable in the same way