AddCallerToLogger adds the calling function to the logger under the "func", "file", and "line" keys.

Close tries to close a closer, ignoring any error.

LoggerWithCaller recovers the calling function of LoggerWithCaller and adds it to the given logger under the "func", "file", and "line" keys.

LoggerWithCallerAtDepth recovers the caller at the given stack depth and adds it to the given logger under the "func", "file", and "line" keys.

OpenOutputFile opens and returns a file for output.