Can't find the way to change this node into a python script

Hi I want to create a Project Parameter only if it doesn’t exist in the document. If it exists I don’t want dynamo to run the “CreateProjectParameter” node. But this node doesn’t have any true/false input to prevent it for been executed if the parameter already exist, so everytime that I run the dynamo it creates the parameter again and again. I CAN NOT use any package, so I was thinking of using a dynamo script, however, I don’t know programing that much (I know basics). Can any one can help me or show me how can achieve this task, either with dynamo nodes or dynamo scripts.

I also tried making it code and apply an if condition to run the “CreateProjectParameter” line only when the result of the previous nodes are true

but it doesn’t work. Even if it is false it always create the parameter


@rafaelPD66Z ,

in you picture… you use a codeblock! thats just for designScript

Check out this



Hello, maybe try this way


Hi @christian.stan it actually does the task. It is a simple and effective solution. However, it creates a warning message, which is not a big deal, but if there is any way to avoid the warning?

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you can consult this topic, should meet your expectations


edit: with Mr. Nick’s script and additional explanations on the modification according to the Python Engine Used (the names of the code blocks are important)


You haven’t provided an input for Spec Types as the warning mentions.

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That’s excellent. I didn’t know you can freeze nodes in real time. Thank you so much

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