Tkinter custom widget styling and creating custom theme

I would like to create a custom theme for my app. I can’t get the button widget to expand in my code below. I can configure the button using the minimum width parameter but it should expand to fit the text as specified under layout.
Any ideas what is wrong with the code below?

import tkinter
from tkinter import ttk

root = tkinter.Tk()

colors = {
          "frame": "#efefef",
          "disabledfg": "#aaaaaa",
          "selectbg": "#657a9e",
          "selectfg": "#ffffff"

style = ttk.Style()
style.theme_create("test", "default", settings={
    ".": {
            {"background": colors['frame'],
             "troughcolor": colors['frame'],
             "selectbackground": colors['selectbg'],
             "selectforeground": colors['selectfg'],
             "fieldbackground": colors['frame'],
             "font": "TkDefaultFont",
             "borderwidth": 1},
        "map": {"foreground": [("disabled", colors['disabledfg'])]}
    "TButton": {
                "configure": {"width": 10, "anchor": "left"},
                "layout": [
                    ("Button.button", {"children":
                        [("Button.focus", {"children":
                            [("Button.padding", {"children":
                                [("Button.label", {"side": "left", "expand": 1})]

button_send = ttk.Button(root, text="TEST BUTTON ONLY!").grid(row=0, column=0, padx=50, pady=50)


Could you provide a screenshot of what you see when you run this?

Also just FYI, Tkinter is technically not “Web Development” since its primarily used to make desktop applications in Python. I’d put this into the general programming category.

Hi, Thanks for response. Please see below a screenshoot. I had this originally set up as a general query, but it was edited by admin and changed to web development. I am not sure why…
The source code for this example is here…