Using a conditional statement to link a button press - python-3.x

Question

The idea is that if one presses one of the buttons the labeled text is inputted in the top left entry box. My initial plan was to use an if statement when the button is pressed and then insert the text according.
However, I am not sure what syntax to use that would allow me to make this one line conditional statement that recognizes the button being pressed. Is this actually possible or do I need to make a separate function?
from tkinter import *
from tkinter import ttk
class GUI():
def __init__(self, master):
self.master = master
master.resizable(True, True)
master.title('Conversion Calculator')
self.tabControl = ttk.Notebook(master)
self.tab1 = ttk.Frame(self.tabControl) # tab set up
self.tabControl.add(self.tab1, text='Builder')
self.tabControl.pack(expand=1, fill="both")
self.builder_entrybox = ttk.Entry(self.tab1, width=24) # entry box set up
self.builder_entrybox.grid(column=0, row=0)
self.builder_outputbox = ttk.Entry(self.tab1, width=24) # output box set up
self.builder_outputbox.grid(column=0, row=1)
self.builder_outputbox.config(state='NORMAL')
self.builder_outputbox.config(state='readonly')
self.CH3_Button = ttk.Button(self.tab1, text='CH3', command=self.builder) # CH3 button
self.CH3_Button.grid(column=1, row=0)
self.CH2_Button = ttk.Button(self.tab1, text='CH2', command=self.builder) # CH2 button
self.CH2_Button.grid(column=2, row=0)
self.OH_Button = ttk.Button(self.tab1, text='OH', command=self.builder) # OH button
self.OH_Button.grid(column=1, row=1)
self.O_Button = ttk.Button(self.tab1, text='O', command=self.builder) # O button
self.O_Button.grid(column=2, row=1)
self.H_Button = ttk.Button(self.tab1, text='H', command=self.builder) # H button
self.H_Button.grid(column=3, row=1)
self.COOH_Button = ttk.Button(self.tab1, text='COOH', command=self.builder) # COOH button
self.COOH_Button.grid(column=3, row=0)
class Logic(GUI):
def builder (self): # adding button text to entry box (tab1)
self.builder_entrybox.insert(0, 'CH3')
if __name__ == "__main__":
root = Tk()
test = Logic(root)

Answer 1

Yes, you would make a new function for every button:
class GUI():
def __init__(self, master):
# ...
self.CH3_Button = ttk.Button(self.tab1, text='CH3', command=self.CH3_builder) # CH3 button
self.CH3_Button.grid(column=1, row=0)
def CH3_builder(self):
self.builder_entrybox.insert('end', 'CH3')
Python can make functions on the fly, either with functools.partial (early binding) or lambda (late binding). Using that you could write the same thing like this:
from functools import partial
class GUI():
def __init__(self, master):
# ...
self.CH3_Button = ttk.Button(self.tab1, text='CH3', command=partial(self.builder_entrybox.insert, 'end', 'CH3')) # CH3 button
self.CH3_Button.grid(column=1, row=0)
But it would be better if you make a small subclass to handle all this for you, which makes your code very reusable and therefore neat:
from tkinter import ttk
import tkinter as tk
class Copa(ttk.Button):
"""A new type of Button that moves the text into a Entry when clicked"""
def __init__(self, master=None, **kwargs):
ttk.Button.__init__(self, master, command=self.builder, **kwargs)
def builder(self):
self.master.builder_entrybox.insert('end', self['text'])
class BuilderFrame(tk.Frame):
def __init__(self, master=None, **kwargs):
tk.Frame.__init__(self, master, **kwargs)
self.builder_entrybox = ttk.Entry(self, width=24) # entry box set up
self.builder_entrybox.grid(column=0, row=0)
self.builder_outputbox = ttk.Entry(self, width=24) # output box set up
self.builder_outputbox.grid(column=0, row=1)
self.builder_outputbox.config(state='NORMAL')
self.builder_outputbox.config(state='readonly')
self.CH3_Button = Copa(self, text='CH3') # CH3 button
self.CH3_Button.grid(column=1, row=0)
self.CH2_Button = Copa(self, text='CH2') # CH2 button
self.CH2_Button.grid(column=2, row=0)
self.OH_Button = Copa(self, text='OH') # OH button
self.OH_Button.grid(column=1, row=1)
self.O_Button = Copa(self, text='O') # O button
self.O_Button.grid(column=2, row=1)
self.H_Button = Copa(self, text='H') # H button
self.H_Button.grid(column=3, row=1)
self.COOH_Button = Copa(self, text='COOH') # COOH button
self.COOH_Button.grid(column=3, row=0)
class GUI():
def __init__(self, master):
self.master = master
master.resizable(True, True)
master.title('Conversion Calculator')
self.tabControl = ttk.Notebook(master)
self.tab1 = BuilderFrame(self.tabControl) # tab set up
self.tabControl.add(self.tab1, text='Builder')
self.tabControl.pack(expand=1, fill="both")
if __name__ == "__main__":
root = tk.Tk()
test = GUI(root)
root.mainloop()