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Find and visualise reference cycles between Python objects.

Project Description

The refcycle package provides support for creating, analysing, and visualising graphs of Python objects and the references between them. Its main intended use is for finding reference cycles amongst Python objects.


  • An ObjectGraph class representing a collection of objects and references.
  • Computation of strongly connected components of the object graph.
  • Ability to export to JSON and reimport later for offline analysis.
  • Export of images via Graphviz.
  • Supports Python 2 and Python 3 (CPython only).


  • Currently requires Python version 2.7 or version >= 3.3. If there’s any interest in Python 2.6 or Python 3.2 support let me know, and I may work on those. It’s unlikely that versions earlier than 2.6 or 3.2 will ever be supported.
  • The export_image method for exporting a graph in image form requires Graphviz to be installed.
  • Uses the six package to support Python 2 and Python 3 from a single codebase.
  • Refcycle is CPython only.


Up-to-date documentation can be found on “Read the Docs”, at

Installing refcycle

The latest release of refcycle is available from the Python Package Index, at On most systems, it can be installed in the usual way using easy_install or pip:

pip install -U refcycle

The currently-in-development version can be obtained from the project’s GitHub homepage:


The refcycle package is copyright (c) 2013 Mark Dickinson.

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

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Filename, Size & Hash SHA256 Hash Help File Type Python Version Upload Date
(40.9 kB) Copy SHA256 Hash SHA256
Wheel py2.py3 Jun 27, 2017
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Source None Jun 27, 2017

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