Based on the Prefect documentation, it seems that you need to register the blocks in Prefect-AWS with

prefect block register -m prefect_aws

. However, the documentation does not provide a direct way to instantiate a block such as an AwsCredentials Block without importing the class AwsCredentials from prefect_aws. The method you're currently using,

_globals()<name=model.name, **model.params|class_name>

, is a common way to dynamically instantiate classes in Python when the class name is only known at runtime. However, this does indeed require that the class is imported into the script. If you want to avoid having to import every type of block that you might use for different customers, you might consider creating a factory function that imports and instantiates the necessary block classes on demand. This would allow you to only import the classes that are actually used in a given script, rather than having to import all possible block classes upfront. Here's a rough example of what this might look like:

def block_factory(class_name, name, params):
    module = importlib.import_module(f"prefect_aws.{class_name}")
    class_ = getattr(module, class_name)
    return class_(name=name, **params)

You could then use this function to instantiate your blocks like so:

block = block_factory(model.class_name, model.name, model.params)

Please note that this is a general Python solution and might need to be adapted to your specific use case and the Prefect-AWS library. If Prefect-AWS provides a better way to handle this, it would be preferable to use that.