# Python Node (Based CPython and IronPython)

**URL:** <https://forum.dynamobim.com/t/python-node-based-cpython-and-ironpython/82460>\
**Category:** Developers\
**Tags:** revit, python, cpython3\
**Created:** [October 26, 2022, 2:39am UTC](https://forum.dynamobim.com/t/python-node-based-cpython-and-ironpython/82460 "2022-10-26T02:39:31Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![manhgt214](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/manhgt214/32/153251_2.png) [@manhgt214](https://forum.dynamobim.com/u/manhgt214)\
**Post date:** [October 26, 2022, 2:39am UTC](https://forum.dynamobim.com/t/python-node-based-cpython-and-ironpython/82460/1 "2022-10-26T02:39:31Z")

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Hi all!

What is defference beetween CPython and IronPython on Python Node

CPython has error: 'Wall object has no attribute LookupParameter  
=\> IronPython ok

 ![image](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/d/4/d42aa74c0ca5450fcca854acd72d24137865005d.png)

 ![image](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/4/3/4321358beb21022d7ba11e8dfddb39e763b13d08.png)

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**Author:** ![mzjensen](https://avatars.discourse-cdn.com/v4/letter/m/b77776/32.png) [@mzjensen](https://forum.dynamobim.com/u/mzjensen)\
**Post date:** [October 26, 2022, 3:07am UTC](https://forum.dynamobim.com/t/python-node-based-cpython-and-ironpython/82460/2 "2022-10-26T03:07:01Z")

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Hi @manhgt214,

The shift from IronPython to Python.NET was made awhile ago. This thread might answer some questions.

> [@\[New Feature Preview\] Python 3 Support Issue Thread](https://forum.dynamobim.com/t/new-feature-preview-python-3-support-issue-thread/51649):
>
> Dear Dynamo Lovers, Greetings from Dynamo Team. We hope you are doing well in this special situation. Today I am writing to give you a preview of the upcoming Python 3 support we will add to Python workflows starting from Dynamo 2.7.x releases. We will keep you in loop with all these changes and hopefully get feedback when things do not make sense jump to your eyes. You will be able to try it out using our daily builds on [dynamobuilds.com](https://dynamobuilds.com/). The new Python node engine lable on lower right corne…

This blog post may also help.

> **[Why has Dynamo Switched to Python 3, Should I Update Too? - Dynamo BIM](https://dynamobim.org/why-has-dynamo-switched-to-python-3-should-i-update-too/)**
>
> Since the introduction of Python 3 in 2008, Python 2 and 3 have been supported side-by-side by the Python Software Foundation (PSF) and the broader Python Community. This stopped on January 1st, 2020 when Python 2 support from the PSF officially...

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**Author:** ![c.poupin](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/c.poupin/32/89152_2.png) [@c.poupin](https://forum.dynamobim.com/u/c.poupin)\
**Post date:** [October 26, 2022, 7:08am UTC](https://forum.dynamobim.com/t/python-node-based-cpython-and-ironpython/82460/3 "2022-10-26T07:08:51Z")

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Hello @manhgt214  
out of curiosity, can you share a sample RVT file for test ?, the bug does not seem to occur on all walls type

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<div class="post-metadata">

**Author:** ![manhgt214](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/manhgt214/32/153251_2.png) [@manhgt214](https://forum.dynamobim.com/u/manhgt214)\
**Post date:** [October 31, 2022, 8:31am UTC](https://forum.dynamobim.com/t/python-node-based-cpython-and-ironpython/82460/4 "2022-10-31T08:31:18Z")

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This is example  
Thank you!

[Project1.rvt](https://forum.dynamobim.com/uploads/short-url/8catUMsWoIxNqqLn8YHlHm2Uvh.rvt) (4.8 MB)

```auto
import clr
clr.AddReference('RevitAPI')
from Autodesk.Revit.DB import *
clr.AddReference('RevitServices')
from RevitServices.Persistence import DocumentManager
doc = DocumentManager.Instance.CurrentDBDocument

Walls = FilteredElementCollector(doc).OfCategory(BuiltInCategory.OST_Walls).WhereElementIsNotElementType().ToElements()

Comments = []

for i in Walls:
	Comments.append(i.LookupParameter('Comments').AsValueString())

OUT = Comments

```

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<div class="post-metadata">

**Author:** ![c.poupin](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/c.poupin/32/89152_2.png) [@c.poupin](https://forum.dynamobim.com/u/c.poupin)\
**Post date:** [October 31, 2022, 11:46am UTC](https://forum.dynamobim.com/t/python-node-based-cpython-and-ironpython/82460/5 "2022-10-31T11:46:10Z")

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@manhgt214  
strange, I did not manage to get this error 🤔

 ![image](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/5/4/54b4ae7d05d3fc8a20e132cc6d5f8fbaa830af6a.png)