Python, Tkinter, StringVar

Here is the code for translating from both Russian to English and vice versa:

import tkinter as tk

window = tk.Tk()

window.title('Boom')
window.geometry('300x200+50+75')
window.resizable(True, True)

# Create two dictionaries: one for Russian to English, the other for English to Russian
fruit_r_to_e = {'яблоко':'apple', "ананас":'pineapple'}
fruit_e_to_r = {english: russian for russian, english in fruit_r_to_e.items()}

mystring = tk.StringVar(window)
my_string1 = tk.StringVar(window)

def getvalue():
    global mystring, my_string1, fruit_e_to_r, fruit_r_to_e

    string = mystring.get()

    # If the string is in English, translate it to Russian
    if string in fruit_e_to_r:
        print(fruit_e_to_r[string])

    # If the string is in Russian, translate it to English
    elif string in fruit_r_to_e:
        print(fruit_r_to_e[string])

    else:
        print("This word is not in the dictionary.")

def info():
    global my_string1
    print(my_string1())

entry = tk.Entry(window, textvariable=mystring, bg='white', fg='black', width=200)
entry.pack()

button = tk.Button(window, 
    text='Translate',
    bg='blue',
    fg='black',
    width=15,
    height=3,
    command=getvalue
)
button.pack()

entry = tk.Entry(window, textvariable=my_string1, bg='white', fg='black', width=200)
entry.pack()

window.mainloop()

I created two dictionaries, one for each translation direction. When getvalue() is called, it checks if the word is in the English dictionary: if string in fruit_e_to_r:, and translates it to Russian if it is. If it isn't, it checks if it is in the Russian dictionary: elif string in fruit_r_to_e:, and translates it to English if it is. If it is not in either dictionary: else:, it shows a message saying that the word is not in either dictionary.

I made a few other changes to the code as well. I removed the from tkinter import *, because you already have tkinter imported in the next line: import tkinter as tk, and because wildcard imports (using from <package> import *) are discouraged.

I also noticed that when you create the widgets, you call .pack() when you assign the widgets to variables, for example you used entry = tk.Entry(...).pack(). This is a problem, because the pack() method returns None, so you won't be able to use the widgets later in the program. You need to call entry = tk.Entry(...), and then call entry.pack() on the next line. This way, the entry variable actually contains an instance of tkinter.Entry, instead of None.

You'll notice that I also used the global statement in the functions. This is not required (unless you're assigning variables), but it's generally a good idea. global tells the function that it's using variables that were defined outside the function. So, global mystring, fruit_e_to_r, fruit_r_to_e tells getvalue() that mystring, fruit_e_to_r, and fruit_r_to_e are all variables that were created outside of getvalue().