old_contents: # -*- coding: utf-8 -*-
  import os
  import pprint
  import warnings
  
  from gpn.node import Node
  
  suffix = '.node'
  suffix_default = '.node-default'
  
  
  class Graph(object):
      def __init__(self, path=None, nodes=None):
          global suffix
          global suffix_default
          assert not path or not nodes, ('Cannot specify both path '
                                              'and nodes.')
          # Get nodes.
          if not nodes:
              if not path:
                  path = os.getcwd()  # Defaule to cwd.
  
              def is_node(x):
                  return x.endswith(suffix) or x.endswith(suffix_default)
              nodes = [Node(x) for x in os.listdir(path) if is_node(x)]
  
              self.path = path
  
          else:
              self.path = '<from collection>'
  
          # Set nodes.
          def node_item(p):
              assert isinstance(p, Node), '%r is not a Node.' % p
              if p.name:
                  key = p.name
              else:
                  key = p.get_hash()[:12]  # <- TODO!!!: Implement get_hash().
                  warnings.warn("Node is unnamed--using "
                                "short hash '%s'." % key)
              return (key, p)
          self.nodes = dict(node_item(p) for p in nodes)
  
          # Set edges.
          self.edges = [None]
  
new_contents: # -*- coding: utf-8 -*-
  import os
  import pprint
  import warnings
  
  from gpn.node import Node
  
  suffix = '.node'
  suffix_default = '.node-default'
  
  
  class Graph(object):
      def __init__(self, path=None, nodes=None):
          global suffix
          global suffix_default
          assert not path or not nodes, ('Cannot specify both path and nodes.')
  
          # Get nodes.
          if not nodes:
              if not path:
                  path = os.getcwd()  # Default to cwd.
  
              def is_node(x):
                  return x.endswith(suffix) or x.endswith(suffix_default)
              nodes = [Node(x) for x in os.listdir(path) if is_node(x)]
  
              self.path = path
  
          else:
              self.path = '<from collection>'
  
          # Set nodes.
          def node_item(p):
              assert isinstance(p, Node), '%r is not a Node.' % p
              if p.name:
                  key = p.name
              else:
                  key = p.get_hash()[:12]  # <- TODO!!!: Implement get_hash().
                  warnings.warn("Node is unnamed--using "
                                "short hash '%s'." % key)
              return (key, p)
          self.nodes = dict(node_item(p) for p in nodes)
  
          # Set edges.
          self.edges = [None]
  
subject: Fix typo and minor formatting.