[Python] Model gets generated with error when parent type is a list of another model

Description

PythonClientCodegen.java doesnt instantiate the map "instantiationTypes" with key "array" and overridden toInstantiationType() has no code block for instace of "ArrayProperty".
Generated model looks like this:

class TopEventOutput(null<TopEventOutputInner>):

Here TopEventOutput is supposed to inherit list of TopEventOutputInner

    @Override
    public String toInstantiationType(Property p) {
        if (p instanceof MapProperty) {
            return instantiationTypes.get("map");
        }
        return null;
    }

Swagger-codegen version

I have checked in 3.0.4. I guess this is common across all versions.

Swagger declaration file content or url

Steps to reproduce

Take any yaml file and make a model which inherits a list of another model.
Although I am not posting the yaml files and code to reproduce it. I have done an RCA and found out the code which causes this issue. i have mentioned the same in description.

Suggest a fix/enhancement

instantiationTypes.put("array", <Appropriate_type>);

Start in PythonClientCodegen.java at instantiationTypes and the overridden toInstantiationType(Property p), then reproduce with a model inheriting a list of another model. Compare the existing map handling with ArrayProperty handling. Done means the generated model uses the appropriate list parent type instead of null.