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: content.go
    path of file: ./repos/juju/core/resources
    
    the code of the file until where you have to start completion: // Copyright 2016 Canonical Ltd.
// Licensed under the AGPLv3, see LICENCE file for details.

package resources

// TODO(ericsnow) Move this file to the charm repo?

import (
	"io"
	"os"

	charmresource "github.com/juju/charm/v12/resource"
	"github.com/juju/errors"
	"github.com/juju/utils/v3"
)

// Content holds a reader for the content of a resource along
// with details
    
func GenerateContent(reader io.ReadSeeker) (Content, error) {
	var sizer utils.SizeTracker
	sizingReader := io.TeeReader(reader, &sizer)
	fp, err := charmresource.GenerateFingerprint(sizingReader)
	if err != nil {
		return Content{}, errors.Trace(err)
	}
	if _, err := reader.Seek(0, os.SEEK_SET); err != nil {
		return Content{}, errors.Trace(err)
	}
	size := sizer.Size()

	content := Content{
		Data:        reader,
		Size:        size,
		Fingerprint: fp,
	}
	return content, nil
}