观察单步执行的情况

> c:\users\cds\documents\python\untitled0.py(1)<module>()
----> 1 import tkinter as tk
      2 t=tk.Tk()
      3 t.geometry('500x58')
      4 c=[]
      5 n=0 #画布数量计数


ipdb> None
> c:\users\cds\documents\python\untitled0.py(2)<module>()
      1 import tkinter as tk
----> 2 t=tk.Tk()
      3 t.geometry('500x58')
      4 c=[]
      5 n=0 #画布数量计数


ipdb> None
> c:\users\cds\documents\python\untitled0.py(3)<module>()
      1 import tkinter as tk
      2 t=tk.Tk()
----> 3 t.geometry('500x58')
      4 c=[]
      5 n=0 #画布数量计数


ipdb> None
> c:\users\cds\documents\python\untitled0.py(4)<module>()
      2 t=tk.Tk()
      3 t.geometry('500x58')
----> 4 c=[]
      5 n=0 #画布数量计数
      6 j=0 #画布间隔


ipdb> None
> c:\users\cds\documents\python\untitled0.py(5)<module>()
      3 t.geometry('500x58')
      4 c=[]
----> 5 n=0 #画布数量计数
      6 j=0 #画布间隔
      7 while n<9:


ipdb> None
> c:\users\cds\documents\python\untitled0.py(6)<module>()
      4 c=[]
      5 n=0 #画布数量计数
----> 6 j=0 #画布间隔
      7 while n<9:
      8     global j


ipdb> None
> c:\users\cds\documents\python\untitled0.py(7)<module>()
      5 n=0 #画布数量计数
      6 j=0 #画布间隔
----> 7 while n<9:
      8     global j
      9     c.append(tk.Canvas(bg='red'))


ipdb> None
> c:\users\cds\documents\python\untitled0.py(9)<module>()
      7 while n<9:
      8     global j
----> 9     c.append(tk.Canvas(bg='red'))
     10     c[n].place(x=j)
     11     j+=55


ipdb> None
> c:\users\cds\documents\python\untitled0.py(10)<module>()
      8     global j
      9     c.append(tk.Canvas(bg='red'))
---> 10     c[n].place(x=j)
     11     j+=55
     12     n+=1


ipdb> None
> c:\users\cds\documents\python\untitled0.py(11)<module>()
      9     c.append(tk.Canvas(bg='red'))
     10     c[n].place(x=j)
---> 11     j+=55
     12     n+=1
     13 tk.mainloop()


ipdb> None
> c:\users\cds\documents\python\untitled0.py(12)<module>()
      9     c.append(tk.Canvas(bg='red'))
     10     c[n].place(x=j)
     11     j+=55
---> 12     n+=1
     13 tk.mainloop()


ipdb> None
> c:\users\cds\documents\python\untitled0.py(7)<module>()
      5 n=0 #画布数量计数
      6 j=0 #画布间隔
----> 7 while n<9:
      8     global j
      9     c.append(tk.Canvas(bg='red'))


ipdb> None
> c:\users\cds\documents\python\untitled0.py(9)<module>()
      7 while n<9:
      8     global j
----> 9     c.append(tk.Canvas(bg='red'))
     10     c[n].place(x=j)
     11     j+=55


ipdb> None
> c:\users\cds\documents\python\untitled0.py(10)<module>()
      8     global j
      9     c.append(tk.Canvas(bg='red'))
---> 10     c[n].place(x=j)
     11     j+=55
     12     n+=1


ipdb> None
> c:\users\cds\documents\python\untitled0.py(11)<module>()
      9     c.append(tk.Canvas(bg='red'))
     10     c[n].place(x=j)
---> 11     j+=55
     12     n+=1
     13 tk.mainloop()


ipdb> None
> c:\users\cds\documents\python\untitled0.py(12)<module>()
      9     c.append(tk.Canvas(bg='red'))
     10     c[n].place(x=j)
     11     j+=55
---> 12     n+=1
     13 tk.mainloop()


ipdb> None
> c:\users\cds\documents\python\untitled0.py(7)<module>()
      5 n=0 #画布数量计数
      6 j=0 #画布间隔
----> 7 while n<9:
      8     global j
      9     c.append(tk.Canvas(bg='red'))

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