binding for map -- used as an input argument

[ffyu-lj]

Data type:
std::map<std::String, std::String> ssmap;
binding code:
dt.cpp (-> import dt)

#include <pybind11/stl.h>
#include <pybind11/stl_bind.h>
#include "./ssmap.h"

PYBIND11_MAKE_OPAQUE(std::map<std::String, std::String>>)

void bind_string(py::module &m)
{
py::classstd::String pyClass(m, "String);
pyClass.def(py::init<const std::String&>(), py::return_value_policy::move);
...
}
void bind_ssmap(py::module &m)
{
py::bind_map<std::String, std::String>>(m, "ssmap");
}
...
Then in another module, I'll use ssmap:
vp.cpp (import vp)

void bind_vp(py::module &m)
{
py::class pyClass(m, "vp", py::module_local());
pyClass.def("reset", &vp::reset, py::arg("val")); ---> val is type of ssmap
}

// test script:
import dt
import vp

val = dt.ssmap()
print("type of val is ", type(val))

str = dt.String("Hi")
val[str]=str

vp.reset(val) --> gave error

Errors: TypeError: reset(): incompatible function arguments. The following argument types are supported:
1. (self: vp, value: Dict[std::String, std::String]) -> None

If I checked the type of val, it shows:
type of val is : <class 'dt.ssmap'>

So why the input argument (val) is taken as Dict, but the ssmap is taken as class of ssmap (but not Dict), Is there a way to match the two?
Thanks!

[ffyu-lj]

Ok, I think the error is due to that ssmap is bind in dt module, then in vp module, the type (ssmap) is used as an input.
If I put the binding of ssmap in the same module as vp, the error is gone.

So the question is if I can only put the binding of ssmap in a different module, is there a solution (binding side)?
I can do: dict(ssmap) in the test script but would like to know if there is a way to do it in the binding code.

Looking for suggestions.
Thanks!