code: def root(path, root):
      """If 'path' is relative, it is rooted at 'root'. Otherwise, it's unchanged."""
      if os.path.isabs(path):
          return path
      else:
          return os.path.join(root, path)
  
imports: import os.path
  from utility import to_seq
  from glob import glob
  from b2.util import bjam_signature
label_desc: Use image node_id 1 for calling a global function with example usage: root(path, root) and returns: path, os