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diff --git a/tools/python/google/path_utils.py b/tools/python/google/path_utils.py
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+# Copyright 2008, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#    * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#    * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#    * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Some utility methods for getting and manipulating paths."""
+
+# TODO(pamg): Have the buildbot use these, too.
+
+
+import errno
+import os
+import sys
+
+class PathNotFound(Exception): pass
+  
+def ScriptDir():
+  """Get the full path to the directory containing the current script."""
+  script_filename = os.path.abspath(sys.argv[0])
+  return os.path.dirname(script_filename)
+
+def FindAncestor(start_dir, ancestor):
+  """Finds an ancestor dir in a path.
+  
+  For example, FindAncestor('c:\foo\bar\baz', 'bar') would return
+  'c:\foo\bar'.  Unlike FindUpward*, this only looks at direct path ancestors.
+  """
+  start_dir = os.path.abspath(start_dir)
+  path = start_dir
+  while True:
+    (parent, tail) = os.path.split(path)
+    if tail == ancestor:
+      return path
+    if not tail:
+      break
+    path = parent
+  raise PathNotFound("Unable to find ancestor %s in %s" % (ancestor, start_dir))
+
+def FindUpwardParent(start_dir, *desired_list):
+  """Finds the desired object's parent, searching upward from the start_dir.
+
+  Searches start_dir and all its parents looking for the desired directory
+  or file, which may be given in one or more path components. Returns the
+  first directory in which the top desired path component was found, or raises
+  PathNotFound if it wasn't.
+  """
+  desired_path = os.path.join(*desired_list)
+  last_dir = ''
+  cur_dir = start_dir
+  found_path = os.path.join(cur_dir, desired_path)
+  while not os.path.exists(found_path):
+    last_dir = cur_dir
+    cur_dir = os.path.dirname(cur_dir)
+    if last_dir == cur_dir:
+      raise PathNotFound('Unable to find %s above %s' %
+                         (desired_path, start_dir))
+    found_path = os.path.join(cur_dir, desired_path)
+  # Strip the entire original desired path from the end of the one found
+  # and remove a trailing path separator, if present.
+  found_path = found_path[:len(found_path) - len(desired_path)]
+  if found_path.endswith(os.sep):
+    found_path = found_path[:len(found_path) - 1]
+  return found_path
+
+
+def FindUpward(start_dir, *desired_list):
+  """Returns a path to the desired directory or file, searching upward.
+
+  Searches start_dir and all its parents looking for the desired directory
+  or file, which may be given in one or more path components. Returns the full
+  path to the desired object, or raises PathNotFound if it wasn't found.
+  """
+  parent = FindUpwardParent(start_dir, *desired_list)
+  return os.path.join(parent, *desired_list)
+
+
+def MaybeMakeDirectory(*path):
+  """Creates an entire path, if it doesn't already exist."""
+  file_path = os.path.join(*path)
+  try:
+    os.makedirs(file_path)
+  except OSError, e:
+    # errno.EEXIST is "File exists".  If we see another error, re-raise.
+    if e.errno != errno.EEXIST:
+      raise