为什么Tkinter Entry输入未反映在我连接到的sql表上？它正在产生空表记录

如何解决为什么Tkinter Entry输入未反映在我连接到的sql表上？它正在产生空表记录

我创建了一个数据库类，其实例应为sql表。它有3种方法：一种创建表，

    def create_table(self,*args):
        c.execute('''CREATE TABLE IF NOT EXISTS {}  {} '''.format(self.table_name,args))
        conn.commit()

一个构造sql INSERT INTO语句的

    def insert_structure(self,mydict,table_name):
        query = 'INSERT INTO {} VALUES ({}{})'
        d = dict(mydict)
        y = next(iter(d))
        # table = d.pop(y)
        columns = ',:'.join(d.keys())
        placeholders = ','.join(['{}'] * len(d))
        values = d.values()
        f = str(query.format(table_name,':',columns,placeholders))
        return f

和一个应该在表中插入值的对象（使用insert_structure方法）。

    def insert_data(self,dicty,list):
        c.execute(self.insert_structure(dicty,self.table_name),dicty)
        conn.commit()
        for k in list:
            k.delete(0,END)

对于GUI，我使用了tkinter，因此当我运行该程序时，会出现一个包含4个条目和一个按钮的窗口

该按钮将insert_data作为命令，并以字典“ dicto”作为参数（我使用lambda，因此应该可以使用）。

dicto = {
                  'cow_id': cow_id.get(),'lactation_phase': lactation_phase.get(),'milk_production': milk_production.get(),'weight': weight.get()
              }
entries = [cow_id,lactation_phase,milk_production,weight ]

cows.create_table('cow_id REAL','lactation_phase TEXT','milk_production REAL','weight REAL')
btn = Button(root,text = "Input cow's data",command = lambda : cows.insert_data(dicto,entries))
btn.place(x = 905,y = 350)

因此，当我单击按钮时，应将在Cow_id，Lationation_phase，milk_production和weight条目中输入的值插入到我创建的表中，但是插入的值是空白的，因此每次单击按钮时，它都会创建一个空记录，并我不知道为什么会这样。

这是所有代码：

import sqlite3
from tkinter import *
x = 0
root = Tk()
cow_id = Entry(root,width = 30)
cow_id.place(x= 340,y= 300 )
lactation_phase = Entry(root,width = 30)
lactation_phase.place(x = 525,y= 300)
milk_production = Entry(root,width = 30)
milk_production.place(x = 710,y = 300)
weight = Entry(root,width = 30)
weight.place(x= 895,y = 300)
cow_id_label = Label(root,text = "Cow Identification Number")
cow_id_label.place(x = 350,y= 270)
lactation_phase_label = Label(root,text= "Lactation phase")
lactation_phase_label.place(x= 545,y = 270)
milk_production_label = Label(root,text = "Milk production")
milk_production_label.place(x = 720,y = 270)
weight_label = Label(root,text = "Weight")
weight_label.place(x = 905,y = 270)
delete_label = Label(root,text = "To delete cow record enter cow ID" )
delete_label.place(x = 475,y = 500)
delete_entry = Entry(root)
delete_entry.place(x= 340,y = 500)
conn = sqlite3.connect("cows.db")
c = conn.cursor()

class databases:
    global c

    def __init__(self,table_name):
        self.table_name = table_name

    def insert_structure(self,placeholders))
        return f
    def create_table(self,args))
        conn.commit()
    def insert_data(self,dicty)
        conn.commit()

        for k in list:
            k.delete(0,END)
        print(dicty)



    def delete_record(self,*args):
        c.execute('''DELETE FROM {} WHERE {} = {}'''.format(self.table_name,args))
        conn.commit()




cows = databases('cow')
dicto = {
                  'cow_id': cow_id.get(),y = 350)
#btn2 = Button(root,text = "Delete",command = cows.delete_record)
#btn2.place(x = 670,y = 500 )
root.mainloop()