def signature(returns, takes):

    out_takes = []
    for arg in takes:
        out_takes.append(_jni_type_spec(arg))

    return "(" + "".join(out_takes) + ")" + _jni_type_spec(returns)
Produces a JNI method signature, taking the provided arguments 
dataset/ETHPy150Open kivy/pyjnius/jnius/signatures.py/signature