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I think the editor you are using is Vi or VIm, is not so difficult to exit and save a file from there. With reference to the image you post, you can see that there is in the corner left the -- INSERT --, this is a mode of the vim editor. To exit from this mode you need to use the esc button, by doing this you enter in a mode called -- NORMAL -- mode. Now you need to do some magic with vim by type:
The : is important because takes you to the -- COMMAND -- mode, then w is use to save the file and q to exit.
Once you press enter, you execute this command and the commit will be create.
This may takes you out and solve the problem, if not reply here what is wrong.
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