def insert_data(self, id, marka, tip_mash):
        self.c.execute('''INSERT INTO marki (id, marka, tip_mash) VALUES (?, ?, ?)''',
                       (id, marka, tip_mash))
        self.conn.commit()

import tkinter as tk
import tkinter.ttk as ttk

import psycopg2

class Main(tk.Frame):
    def __init__(self, root):
        super().__init__(root)
        self.init_main()
        self.db = db
        self.view_records()

    def init_main(self):
        toolbar = tk.Frame(bg='#d7d8e0')
        toolbar.pack(side=tk.TOP, fill=tk.X)

        self.add_img = tk.PhotoImage(file='add.gif')
        btn_open_dialog = tk.Button(toolbar, text='Добавить позицию', command=self.open_dialog, bg='#d7d8e0', bd=0,
                                    compound=tk.TOP, image=self.add_img)

        btn_open_dialog.pack(side=tk.LEFT)

        self.tree = ttk.Treeview(self, columns=('id', 'marka', 'tip_mash'), height=15, show='headings')

        self.tree.column('id', width=40, anchor=tk.CENTER)
        self.tree.column('marka', width=150, anchor=tk.CENTER)
        self.tree.column('tip_mash', width=200, anchor=tk.CENTER)

        self.tree.heading('id', text='id')
        self.tree.heading('marka', text='Марка')
        self.tree.heading('tip_mash', text='Тип машины')

        self.tree.pack()

    def records(self, id, marka, tip_mash):
        self.db.insert_data(id, marka, tip_mash)
        self.view_records()

    def view_records(self):
        self.db.c.execute('''SELECT * FROM marki ORDER BY id''')
        [self.tree.delete(i) for i in self.tree.get_children()]
        [self.tree.insert('', 'end', values=row) for row in self.db.c.fetchall()]

    def open_dialog(self):
        Child()
        

class Child(tk.Toplevel):
    def __init__(self):
        super().__init__(root)
        self.init_child()
        self.view = app
        
    def init_child(self):
        self.title('Добавить данные в Марки')
        self.geometry('400x220+400+300')
        self.resizable(False, False)

        label_id = tk.Label(self, text='id')
        label_id.place(x=50, y=50)

        label_marka = tk.Label(self, text='Марка')
        label_marka.place(x=50, y=80)

        label_tip = tk.Label(self, text='Тип машины')
        label_tip.place(x=50, y=110)

        ###################################
        self.entry_id = ttk.Entry(self)
        self.entry_id.place(x=200, y=50)

        self.entry_marka = ttk.Entry(self)
        self.entry_marka.place(x=200, y=80)

        self.combobox = ttk.Combobox(self, values=[u'Трактор', u'Комбайн', u'Сеялка', u'Жатка', u'Подборщик'])
        self.combobox.current(0)

        self.combobox.place(x=200, y=110)

        btn_cancel = ttk.Button(self, text='Закрыть', command=self.destroy)
        btn_cancel.place(x=300, y=170)

        btn_ok = ttk.Button(self, text='Добавить')
        btn_ok.place(x=220, y=170)
        btn_ok.bind('<Button-1>', lambda event: self.view.records(self.entry_id.get(),
                                                                 self.entry_marka.get(),
                                                                 self.combobox.get()))

        self.grab_set()
        self.focus_set()

class DB:
    def __init__(self):
        self.conn = psycopg2.connect(database ="agro1", user = "postgres",
                                     password = "postgres", host = "localhost",
                                     port = "5432")
        self.c = self.conn.cursor()

    def insert_data(self, id, marka, tip_mash):
        self.c.execute('''INSERT INTO marki (id, marka, tip_mash) VALUES (?, ?, ?)''',
                       (id, marka, tip_mash))
        self.conn.commit()
        
            
if __name__ == "__main__":
    root = tk.Tk()
    db = DB() 
    app = Main(root)
    app.pack()    
    root.title("Склад запасных частей")
    root.geometry("1400x750+100+50")
    root.resizable(False, False)
    root.mainloop()    

def insert_data(self, id, marka, tip_mash):
        self.c.execute('''INSERT INTO marki (id, marka, tip_mash) VALUES (%s, %s, %s)''',
                       (id, marka, tip_mash))
        self.conn.commit()