Setting sourceDirs without java plugin

Given the following build.gradle:

plugins {
    id "ru.vyarus.use-python" version "2.2.0"
    id "idea"
}

python {
    minPythonVersion = '3.7'

    pip 'aiohttp[speedups]:3.6.2'
    pip 'curl:0.0.1'
    pip 'validators:0.14.3'
    pip 'simple_rest_client:1.0.5'
    pip 'prompt_toolkit:3.0.2'
}

task run(type: PythonTask) {
    command = "clipy.py"
    workDir = "src"
}

idea {
    module {
        sourceDirs += file('src')
        resourceDirs += file('mock-rest-api')
        excludeDirs += file('mock-rest-api/node_modules')
    }
}

I expect that, when I open Module Settings, that this module would have the "src" directory marked as a source directory.
I see the excluded directory "mock-rest-api/node_modules", but not the source directory.

https://www.dropbox.com/s/mcnt8c242wl4h75/Screenshot%202020-05-11%2017.01.09.png?dl=0

I can get it to appear by applying the "java" plugin, as seen below, but should that be necessary, given that this is a Python project?

plugins {
    id "ru.vyarus.use-python" version "2.2.0"
    id "java"
    id "idea"
}

python {
    minPythonVersion = '3.7'

    pip 'aiohttp[speedups]:3.6.2'
    pip 'curl:0.0.1'
    pip 'validators:0.14.3'
    pip 'simple_rest_client:1.0.5'
    pip 'prompt_toolkit:3.0.2'
}

task run(type: PythonTask) {
    command = "clipy.py"
    workDir = "src"
}

idea {
    module {
        sourceDirs += file('src')
        resourceDirs += file('mock-rest-api')
        excludeDirs += file('mock-rest-api/node_modules')
    }
}