# Dynamo for Revit: Python Error

**URL:** <https://forum.dynamobim.com/t/dynamo-for-revit-python-error/52035>\
**Category:** Uncategorized\
**Tags:** revit, python, dynamo\
**Created:** [June 18, 2020, 5:45pm UTC](https://forum.dynamobim.com/t/dynamo-for-revit-python-error/52035 "2020-06-18T17:45:13Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![jk5M9YP](https://avatars.discourse-cdn.com/v4/letter/j/6a8cbe/32.png) [@jk5M9YP](https://forum.dynamobim.com/u/jk5M9YP)\
**Post date:** [June 18, 2020, 5:45pm UTC](https://forum.dynamobim.com/t/dynamo-for-revit-python-error/52035/1 "2020-06-18T17:45:13Z")

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Hello everybody,  
I have the following problem:

* * *

Traceback (most recent call last):  
File “”, line 23, in   
AttributeError: ‘FamilyInstance’ object has no attribute ‘Symbol’

* * *

And here is the Pythonskript:

# Phython-Unterstützung aktivieren und DesignScript-Bibliothek laden

import clr

clr.AddReference(“RevitAPI”)

paramCollection = IN[0]  
objCollection = IN[1]

valueList = list()

for i, objList in enumerate(objCollection):  
for obj in objList:  
\_valueList = list()  
for param in paramCollection[i]:  
\_valueList.append(obj.Symbol.LookupParameter(param).AsValueString())  
valueList.append(\_valueList)

OUT = valueList

I’m just getting stuck and hope you can help me with that.

Best Greatings  
Jan

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**Author:** ![Nick\_Boyts](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/nick_boyts/32/76313_2.png) [@Nick\_Boyts](https://forum.dynamobim.com/u/Nick_Boyts)\
**Post date:** [June 18, 2020, 8:12pm UTC](https://forum.dynamobim.com/t/dynamo-for-revit-python-error/52035/2 "2020-06-18T20:12:12Z")

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For future reference please format python code as “`Preformatted text`” (the `</>` icon) so that it retains its formatting.

One of your objects may not have a FamilySymbol. Can you show us your list of inputs?

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**Author:** ![jk5M9YP](https://avatars.discourse-cdn.com/v4/letter/j/6a8cbe/32.png) [@jk5M9YP](https://forum.dynamobim.com/u/jk5M9YP)\
**Post date:** [June 19, 2020, 9:02am UTC](https://forum.dynamobim.com/t/dynamo-for-revit-python-error/52035/3 "2020-06-19T09:02:39Z")

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Englisch

Hello Nick, thanks for your feedback. I was able to solve the problem last night. I had a mistake in my thinking.

Greatings  
Jan

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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:** [June 19, 2020, 12:10pm UTC](https://forum.dynamobim.com/t/dynamo-for-revit-python-error/52035/4 "2020-06-19T12:10:01Z")

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Hello @jk5M9YP  
your import is incomplete and you need to unwrap yours inputs for using the Revit API

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