#Study Notes and Coraline
Create checksum for Gemfile being bundled.
- If the Gemfile.lock exists, look for the checksum (of the Gemfile).
- Loading the lockfile: Bundler#locked_gems #L140
- returns a LockfileParser object that is accessed through Bundler#locked_gems
 
 - Accessible through #LockfileParser@checksum, in otherwords, 
Bundler#locked_gems.checksumorDefinition#locked_gems.checksum 
 - Loading the lockfile: Bundler#locked_gems #L140
 - When writing lockfile, generate checksum
- Writing the lockfile: [Definition#to_lock #L356]