code: def commit_hash(self):
          
          commit_hash = None
          branch = None
          branch_file = '.git/HEAD'  # ref: refs/heads/develop
  
          # get current branch
          if os.path.isfile(branch_file):
              with open(branch_file, 'r') as f:
                  try:
                      branch = f.read().strip().split('/')[2]
                  except IndexError:
                      pass
  
              # get commit hash
              if branch:
                  hash_file = '.git/refs/heads/{}'.format(branch)
                  if os.path.isfile(hash_file):
                      with open(hash_file, 'r') as f:
                          commit_hash = f.read().strip()
          return commit_hash
docs: Return the current commit hash if available.
  
          This is not a required task so best effort is fine. In other words this is not guaranteed
          to work 100% of the time.