Well consider some data that looks like "2019-12-12 00:00:01","2012-01-01 01:01:01" I wish to replace it so they are valid datetime json values: "2019-12-12T00:00:01+01","2012-01-01T01:01:01+01" I tried writing the following sed command: sed 's/"([0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9])...