from tkinter import *

class Btn:
    def __init__(self, master, color, col_name):
        self.but = Button(master, bg = color, width = 25, text = col_name)
        self.but.pack()

        self.but['command'] = self.pressed
        self.color = color
        self.col_name = col_name

    def pressed(self):
        lbl['text'] = self.col_name
        ent.delete(0, END)
        ent.insert(0, self.color)

root = Tk()
lbl = Label()
lbl.pack()

ent = Entry()
ent.pack()



Btn(root, '#ff0000', 'Красный')
Btn(root, '#ffd700', 'Orange')
Btn(root, '#ffff00', 'Yellow')
Btn(root, '#00ff00', 'Green')
Btn(root, '#007f00', 'Light Blue')
Btn(root, '#0000ff', 'Blue')
Btn(root, '#7f00ff', 'Violet')



root.mainloop()