You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: stacktrace.go
    path of file: ./repos/octant/vendor/go.uber.org/zap
    
    the code of the file until where you have to start completion: // Copyright (c) 2016 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT
    
func takeStacktrace(skip int) string {
	buffer := bufferpool.Get()
	defer buffer.Free()
	programCounters := _stacktracePool.Get().(*programCounters)
	defer _stacktracePool.Put(programCounters)

	var numFrames int
	for {
		// Skip the call to runtime.Callers and takeStacktrace so that the
		// program counters start at the caller of takeStacktrace.
		numFrames = runtime.Callers(skip+2, programCounters.pcs)
		if numFrames < len(programCounters.pcs) {
			break
		}
		// Don't put the too-short counter slice back into the pool; this lets
		// the pool adjust if we consistently take deep stacktraces.
		programCounters = newProgramCounters(len(programCounters.pcs) * 2)
	}

	i := 0
	frames := runtime.CallersFrames(programCounters.pcs[:numFrames])

	// Note: On the last iteration, frames.Next() returns false, with a valid
	// frame, but we ignore this frame. The last frame is a a runtime frame which
	// adds noise, since it's only either runtime.main or runtime.goexit.
	for frame, more := frames.Next(); more; frame, more = frames.Next() {
		if i != 0 {
			buffer.AppendByte('\n')
		}
		i++
		buffer.AppendString(frame.Function)
		buffer.AppendByte('\n')
		buffer.AppendByte('\t')
		buffer.AppendString(frame.File)
		buffer.AppendByte(':')
		buffer.AppendInt(int64(frame.Line))
	}

	return buffer.String()
}