You can try this https://github.com/amol-/dukpy which is a combo of Python and C and offers limited TypeScript compilation capabilities.

In general you might be better off using a native TypeScript compiler and call it from Python instead

Python unlike JavaScript is strong typed so the need for something like typescript is lessened.

Instead you can use type annotations and either the mypy linter or your ides linter to enforce the typing.

In effect, this gives you all the same benefits as typescript without much overhead.

For the code completion and type hinting in IDEs, just add static typing for the Person and Address classes and you are already good to go. Assuming you use the latest python3.6, here's a rough equivalent of the typescript classes from your example:

# spam.py
from typing import Optional, Sequence


class Address:
    street: str
    housenumber: int
    housenumber_postfix: Optional[str]

    def __init__(self, street: str, housenumber: int, 
                 housenumber_postfix: Optional[str] = None) -> None:
        self.street = street
        self.housenumber = housenumber
        self.housenumber_postfix = housenumber_postfix


class Person:
    name: str
    adresses: Sequence[Address]

    def __init__(self, name: str, adresses: Sequence[str]) -> None:
        self.name = name
        self.adresses = adresses


person = Person('Joe', [
    Address('Sesame', 1), 
    Address('Baker', 221, housenumber_postfix='b')
])  # type: Person

I suppose the boilerplate you mentioned emerges when adding the class constructors. This is indeed inavoidable. I would wish default constructors were generated at runtime when not declared explicitly, like this:

class Address:
    street: str
    housenumber: int
    housenumber_postfix: Optional[str]


class Person:
    name: str
    adresses: Sequence[Address]


if __name__ == '__main__':
    alice = Person('Alice', [Address('spam', 1, housenumber_postfix='eggs')])
    bob = Person('Bob', ())  # a tuple is also a sequence

but unfortunately you have to declare them manually.

Edit

As Michael0x2a pointed out in the comment, the need for default constructors is made avoidable in python3.7 which introduced a @dataclass decorator, so one can indeed declare:

@dataclass
class Address:
    street: str
    housenumber: int
    housenumber_postfix: Optional[str]


@dataclass
class Person:
    name: str
    adresses: Sequence[Address]

and get the default impl of several methods, reducing the amount of boilerplate code. Check out PEP 557 for more details.

I guess you could see stub files that can be generated from your code, as some kind of interface files:

$ stubgen spam  # stubgen tool is part of mypy package
Created out/spam.pyi

The generated stub file contains the typed signatures of all non-private classes and functions of the module without implementation:

# Stubs for spam (Python 3.6)
#
# NOTE: This dynamically typed stub was automatically generated by stubgen.

from typing import Optional, Sequence

class Address:
    street: str
    housenumber: int
    housenumber_postfix: Optional[str]
    def __init__(self, street: str, housenumber: int, housenumber_postfix: Optional[str]=...) -> None: ...

class Person:
    name: str
    adresses: Sequence[Address]
    def __init__(self, name: str, adresses: Sequence[str]) -> None: ...

person: Person

These stub files are also recognized by IDEs and if your original module is not statically typed, they will use the stub file for type hints and code completion.

You can run the python script in node using exec(): https://nodejs.org/api/child_process.html#child_processexeccommand-options-callback

A minimal example assuming you have python3 installed on the machine running your node script could be:

// shell.py

print('printed in python')

// server.js

import {exec} from 'child_process'
//if you don't use module use this line instead:
// const { exec } = require('child_process')

exec('python3 shell.py', (error, stdout, stderr) => {
  if (error) {
    console.log(`error: ${error.message}`);
  }
  else if (stderr) {
    console.log(`stderr: ${stderr}`);
  }
  else {
    console.log(stdout);
  }
})

// using it in the shell

% node server.js

// should output this:

printed in python

This way you could traverse your XML file, change it and output it to the js/ts file, or save it as a file and just read that via your js/ts code.