ROS2: Using parameters in a class (Python) - No output before Ctrl+C

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Hello,

I'm new to ROS2 but have previously worked with ROS Kinetic. I have built ROS2 Foxy on 64-bit Windows 10 and currently going through tutorials in Tutorial: Using parameters in a class (Python), which involves declaring a parameter and then changing it dynamically via terminal and launch file. The node runs fine with ros2 run python_parameters param_talker and I can change the parameter in a terminal, but when re-parametering through a launch file, it seems to completely stall and won't output anything via self.get_logger().info(). That is, until I hit Ctrl+C, at which point the node spins once with the new parameter before termination.

Output:

C:\dev_ws>ros2 launch python_parameters python_parameters_launch.py
[INFO] [launch]: Default logging verbosity is set to INFO
[INFO] [param_talker.EXE-1]: process started with pid [3264]
[WARNING] [launch]: user interrupted with ctrl-c (SIGINT)
[ERROR] [param_talker.EXE-1]: process has died [pid 3264, exit code 3221225786, cmd 'C:\dev_ws\install\lib\python_parameters\param_talker.EXE --ros-args -r __node:=custom_parameter_node --params-file C:\Users\h25902\AppData\Local\Temp\launch_params_c0x3kned'].
[param_talker.EXE-1] [INFO] [1600066038.332151500] [custom_parameter_node]: Hello earth!

Node (\dev_ws\src\python_parameters\python_parameters\python_parameters_node.py):

import rclpy
import rclpy.node
from rclpy.exceptions import ParameterNotDeclaredException
from rcl_interfaces.msg import ParameterType

class MinimalParam(rclpy.node.Node):
    def __init__(self):
        super().__init__('minimal_param_node')
        timer_period = 2  # seconds
        self.timer = self.create_timer(timer_period, self.timer_callback)

        self.declare_parameter("my_parameter")

    def timer_callback(self):
        # First get the value parameter "my_parameter" and get its string value
        my_param = self.get_parameter("my_parameter").get_parameter_value().string_value

        # Send back a hello with the name
        self.get_logger().info('Hello %s!' % my_param)

        # Then set the parameter "my_parameter" back to string value "world"
        my_new_param = rclpy.parameter.Parameter(
            "my_parameter",
            rclpy.Parameter.Type.STRING,
            "world"
        )
        all_new_parameters = [my_new_param]
        self.set_parameters(all_new_parameters)

def main():
    rclpy.init()
    node = MinimalParam()
    rclpy.spin(node)

if __name__ == '__main__':
    main()

Setup.py (\dev_ws\src\python_parameters\setup.py):

from setuptools import setup
import os
from glob import glob

package_name = 'python_parameters'

setup(
    name=package_name,
    version='0.0.0',
    packages=[package_name],
    data_files=[
        ('share/ament_index/resource_index/packages',
            ['resource/' + package_name]),
        ('share/' + package_name, ['package.xml']),
        (os.path.join('share', package_name), glob('launch/*_launch.py'))
    ],
    install_requires=['setuptools'],
    zip_safe=True,
    maintainer='Todo Todo',
    maintainer_email='todo.todo@todo.fi',
    description='Python parameter tutorials',
    license='TODO: LICENSE DECLARATION',
    tests_require=['pytest'],
    entry_points={
        'console_scripts': [
            'param_talker = python_parameters.python_parameters_node:main',
        ],
    },
)

Launch file (\dev_ws\src\python_parameters\launch\python_parameters_launch.py):

from launch import LaunchDescription
from launch_ros.actions import Node

def generate_launch_description():
    return LaunchDescription([
        Node(
            package="python_parameters",
            executable="param_talker",
            name="custom_parameter_node",
            output="screen",
            emulate_tty=True,
            parameters=[
                {"my_parameter": "earth"}
            ]
        )
    ])

Does anybody have previous experiences/any reason what's causing this? I tried the C++ version of the tutorial (which works fine), but I'd prefer using Python with ROS2 later on.

Thank you in advance!

EDIT: This appears to be the case for all launch files created in a Python package. Any thoughts?