TeXStudio does not recognize \colon

What is the file to load the command \colon to be recognized (as a known command) by TeXStudio? If I add it to the personal command it works but I guess that this command comes from some package.

ps: I'm talking about highlighting unknown commands.

ps2: I tried grep colon *.cwl on my .config/texstudio folder and I found

mathabx.cwl:\coloneq#Smmathabx.cwl:\eqcolon#Smmathtools.cwl:\vcentcolon#Smathtools.cwl:\ordinarycolon#Smathtools.cwl:\MT_activate_colon#Smathtools.cwl:\MT_active_colon_true#S

that is, no \colon command.