There is a cyclic import in dmprof

tools/deep_memory_profiler/lib/dumplist.py

+# Copyright 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import logging
+
+from lib.deep_dump import DeepDump
+
+LOGGER = logging.getLogger('dmprof')
+
+class DumpList(object):
+  """Represents a sequence of heap profile dumps.
+
+  Individual dumps are loaded into memory lazily as the sequence is accessed,
+  either while being iterated through or randomly accessed.  Loaded dumps are
+  not cached, meaning a newly loaded Dump object is returned every time an
+  element in the list is accessed.
+  """
+
+  def __init__(self, dump_path_list):
+    self._dump_path_list = dump_path_list
+
+  @staticmethod
+  def load(path_list):
+    return DumpList(path_list)
+
+  def __len__(self):
+    return len(self._dump_path_list)
+
+  def __iter__(self):
+    for dump in self._dump_path_list:
+      yield DeepDump.load(dump)
+
+  def __getitem__(self, index):
+    return DeepDump.load(self._dump_path_list[index])