PyJulia Custom Structure Dispatch

Hello, I've got a quistion as for the PyJulia functionality. How do I dispatch a Julia method for different objects defined in Python?

I assume the existence of an underlying mapping between native Python and Julia types: `int` -> `Integer`, `float` -> `Float64`, but at the same time `np.array` -> `Array`, which makes me think that I can customize this sort of mapping and connect `MyClassPy` -> `MyClassJulia`. Is that so?

Thank you in advance!

### example.py

```python
class MyClassA:
pass

class MyClassB:
pass

from julia import Julia
julia = Julia()
julia.eval("@eval Main import Base.MainInclude: include")
from julia import Main
Main.include("example.jl")

foo(MyClassA()) # "Dispatched to MyClassA version"

foo(MyClassB()) # "Dispatched to MyClassB version"
```

### example.jl

```julia
# How can I access MyClassA and MyClassB types in Julia?
some_magic_way_to_include_structures_defined_in_python()

function foo( custom_pyobject :: MyClassA )
println("Dispatched to MyClassA version")
end

function foo( custom_pyobject :: MyClassB )
println("Dispatched to MyClassB version")
end
```