需要用户能够一次输入最多三个字母，以便python turtle绘制

我有所有的代码，可以一次输入一个字母，但由于某些原因，我无法想出如何使它，所以用户可以输入多达三个字母海龟画。这是到目前为止我的代码。任何帮助都将不胜感激，提前谢谢你

import turtle
velcro = turtle.Turtle()
wn = turtle.Screen()
wn.bgcolor('pink')
velcro.color("purple", "blue")
velcro.color()
('purple', 'blue')
velcro.pensize("12")

def color_purple():
  velcro.color ('purple')
def color_blue():
  velcro.color('blue')
def color_black():
  velcro.color ('black')


velcroColor = turtle.textinput("pick a color", "please chose from the colors purple, blue or black, to draw in")
if (velcroColor == 'purple'):
  color_purple()
elif (velcroColor == 'blue'):
  color_blue()
elif (velcroColor == 'black'):
  color_black()


def letter_A():
  velcro.left(90)
  velcro.forward(150)
  velcro.right(90)
  velcro.forward(150)
  velcro.right(90)
  velcro.forward(150)
  velcro.right(180)
  velcro.forward(75)
  velcro.left(90)                             
  velcro.forward(150)                        

def letter_B():
  velcro.left(90)
  velcro.forward(150)
  velcro.right(90)
  velcro.forward(80)
  velcro.right(90)
  velcro.forward(80)
  velcro.right(90)
  velcro.forward(80)
  velcro.right(180)
  velcro.forward(95)
  velcro.right(90)
  velcro.forward(80)
  velcro.right(90)
  velcro.forward(93)

def letter_C():
  velcro.right(90)
  velcro.forward(150)
  velcro.left(90)
  velcro.forward(150)
  velcro.left(180)
  velcro.forward(150)
  velcro.right(90)
  velcro.forward(200)
  velcro.right(90)
  velcro.forward(150)

def letter_D():
  velcro.left(90)
  velcro.forward(200)
  velcro.right(98)
  velcro.forward(180)
  velcro.right(85)
  velcro.forward(200)
  velcro.right(96)
  velcro.forward(172)

def letter_E():
  velcro.right(90)
  velcro.forward(200)
  velcro.left(90)
  velcro.forward(155)
  velcro.left(180)
  velcro.forward(155)
  velcro.right(90)
  velcro.forward(250)
  velcro.right(90)
  velcro.forward(155)
  velcro.left(180)
  velcro.forward(155)
  velcro.left(90)
  velcro.forward(125)
  velcro.left(90)
  velcro.forward(150)

def letter_F():
  velcro.right(90)
  velcro.forward(200)
  velcro.right(180)
  velcro.forward(250)
  velcro.right(90)
  velcro.forward(150)
  velcro.left(180)
  velcro.forward(150)
  velcro.left(90)
  velcro.forward(95)
  velcro.left(90)
  velcro.forward(125)


def letter_G():
  velcro.left(90)
  velcro.forward(200)
  velcro.right(90)
  velcro.forward(155)
  velcro.right(180)
  velcro.forward(155)
  velcro.left(90)
  velcro.forward(225)
  velcro.left(90)
  velcro.forward(175)
  velcro.left(90)
  velcro.forward(80)
  velcro.left(90)
  velcro.forward(80)


def letter_H():
  velcro.forward(150)
  velcro.right(90)
  velcro.forward(175)
  velcro.right(180)
  velcro.forward(300)
  velcro.left(180)
  velcro.forward(125)
  velcro.right(90)
  velcro.forward(150)
  velcro.right(90)
  velcro.forward(125)
  velcro.right(180)
  velcro.forward(300)


def letter_I():
  velcro.left(90)
  velcro.forward(150)
  velcro.left(90)
  velcro.forward(100)
  velcro.right(180)
  velcro.forward(200)
  velcro.right(180)
  velcro.forward(100)
  velcro.left(90)
  velcro.forward(250)
  velcro.right(90)
  velcro.forward(100)
  velcro.right(180)
  velcro.forward(200)

def letter_J():
  velcro.left(90)
  velcro.forward(150)
  velcro.left(90)
  velcro.forward(100)
  velcro.left(180)
  velcro.forward(200)
  velcro.left(180)
  velcro.forward(100)
  velcro.left(90)
  velcro.forward(250)
  velcro.right(90)
  velcro.forward(100)
  velcro.right(90)
  velcro.forward(95)

def letter_K():
  velcro.left(90)
  velcro.forward(200)
  velcro.left(180)
  velcro.forward(100)
  velcro.left(145)
  velcro.forward(100)
  velcro.left(180)
  velcro.forward(100)
  velcro.left(85)
  velcro.forward(150)

def letter_L():
  velcro.left(90)
  velcro.forward(250)
  velcro.left(180)
  velcro.forward(300)
  velcro.left(90)
  velcro.forward(200)

def letter_M():
  velcro.left(90)
  velcro.forward(250)
  velcro.right(140)
  velcro.forward(200)
  velcro.left(100)
  velcro.forward(200)
  velcro.right(140)
  velcro.forward(250)

def letter_N():
  velcro.left(90)
  velcro.forward(200)
  velcro.right(140)
  velcro.forward(250)
  velcro.left(140)
  velcro.forward(200)

def letter_O():
  velcro.left(180)
  velcro.forward(100)
  velcro.right(90)
  velcro.forward(250)
  velcro.right(90)
  velcro.forward(100)
  velcro.right(90)
  velcro.forward(250)

def letter_P():
  velcro.left(90)
  velcro.forward(250)
  velcro.right(90)
  velcro.forward(95)
  velcro.right(90)
  velcro.forward(95)
  velcro.right(90)
  velcro.forward(95)

def letter_Q():
  velcro.left(90)
  velcro.forward(250)
  velcro.left(90)
  velcro.forward(150)
  velcro.left(90)
  velcro.forward(250)
  velcro.left(90)
  velcro.forward(150)
  velcro.left(140)
  velcro.forward(50)
  velcro.left(180)
  velcro.forward(100)

def letter_R():
  velcro.left(90)
  velcro.forward(250)
  velcro.right(90)
  velcro.forward(100)
  velcro.right(90)
  velcro.forward(115)
  velcro.right(90)
  velcro.forward(100)
  velcro.left(135)
  velcro.forward(180)

def letter_S():
  velcro.right(90)
  velcro.forward(150)
  velcro.right(90)
  velcro.forward(150)
  velcro.left(180)
  velcro.forward(150)
  velcro.left(90)
  velcro.forward(150)
  velcro.left(90)
  velcro.forward(150)
  velcro.right(90)
  velcro.forward(150)
  velcro.right(90)
  velcro.forward(150)

def letter_T():
  velcro.left(90)
  velcro.forward(150)
  velcro.left(90)
  velcro.forward(50)
  velcro.right(180)
  velcro.forward(100)

def letter_U():
  velcro.left(90)
  velcro.forward(200)
  velcro.left(180)
  velcro.forward(200)
  velcro.right(90)
  velcro.forward(150)
  velcro.right(90)
  velcro.forward(200)

def letter_V():
  velcro.left(115)
  velcro.forward(250)
  velcro.left(180)
  velcro.forward(250)
  velcro.left(120)
  velcro.forward(250)

def letter_W():
  velcro.left(270)
  velcro.forward(275)
  velcro.right(140)
  velcro.forward(200)
  velcro.left(100)
  velcro.forward(200)
  velcro.right(140)
  velcro.forward(275)

def letter_X():
  velcro.left(140)
  velcro.forward(300)
  velcro.left(180)
  velcro.forward(150)
  velcro.right(270)
  velcro.forward(150)
  velcro.right(180)
  velcro.forward(300)

def letter_Y():
  velcro.left(140)
  velcro.forward(200)
  velcro.left(180)
  velcro.forward(200)
  velcro.right(275)
  velcro.forward(200)
  velcro.left(180)
  velcro.forward(200)
  velcro.left(45)
  velcro.forward(250)

def letter_Z():
  velcro.forward(225)
  velcro.left(140)
  velcro.forward(300)
  velcro.right(140)
  velcro.forward(225)



velcroLetter = turtle.textinput("Turtle alphabet", "please enter a capital letter from A-Z to draw:")
if (velcroLetter == 'a' or velcroLetter == 'A'):
   letter_A()
elif (velcroLetter == 'b' or velcroLetter == 'B'):
   letter_B()
elif (velcroLetter == 'c' or velcroLetter == 'C'):
   letter_C()
elif (velcroLetter == 'd' or velcroLetter == 'D'):
   letter_D()
elif (velcroLetter == 'e' or velcroLetter == 'E'):
   letter_E()
elif (velcroLetter == 'f' or velcroLetter == 'F'):
   letter_F()
elif (velcroLetter == 'g' or velcroLetter == 'G'):
   letter_G()
elif (velcroLetter == 'h' or velcroLetter == 'H'):
   letter_H()
elif (velcroLetter == 'i' or velcroLetter == 'I'):
   letter_I()
elif (velcroLetter == 'j' or velcroLetter == 'J'):
   letter_J()
elif (velcroLetter == 'k' or velcroLetter == 'K'):
   letter_K()
elif (velcroLetter == 'l' or velcroLetter == 'L'):
   letter_L()
elif (velcroLetter == 'm' or velcroLetter == 'M'):
   letter_M()
elif (velcroLetter == 'n' or velcroLetter == 'N'):
   letter_N()
elif (velcroLetter == 'o' or velcroLetter == 'O'):
   letter_O()
elif (velcroLetter == 'p' or velcroLetter == 'P'):
   letter_P()
elif (velcroLetter == 'q' or velcroLetter == 'Q'):
   letter_Q()
elif (velcroLetter == 'r' or velcroLetter == 'R'):
   letter_R()
elif (velcroLetter == 's' or velcroLetter == 'S'):
   letter_S()
elif (velcroLetter == 't' or velcroLetter == 'T'):
   letter_T()
elif (velcroLetter == 'u' or velcroLetter == 'U'):
   letter_U()
elif (velcroLetter == 'v' or velcroLetter == 'V'):
   letter_V()
elif (velcroLetter == 'w' or velcroLetter == 'W'):
   letter_W()
elif (velcroLetter == 'x' or velcroLetter == 'X'):
   letter_X()
elif (velcroLetter == 'y' or velcroLetter == 'Y'):
   letter_Y()
elif (velcroLetter == 'z' or velcroLetter == 'Z'):
   letter_Z()


turtle.mainloop()

---

可能是因为你一次输入了多个字母。然后，您的程序检查e。G“ABC”与“A”匹配。尝试输入单个字母。

因为字母是相对于原点（0，0）打印的，所以技巧是将屏幕分成几个部分（比如三分之一），对于每个字母，在绘制字母之前，移动到相应部分的中心

我已经修改了下面的代码来完成上面的操作（最多三个字母），并简化了一些逻辑。字母函数本身没有变化，因此我省略了下面的大部分，只需在那里拼接原始代码即可：

from turtle import Turtle, Screen

SCREEN_WIDTH, SCREEN_HEIGHT = 1200, 600
SCREEN_MARGIN = 0.1 * SCREEN_WIDTH
MAXIMUM_CHARACTERS = 3
CHARACTER_WIDTH = (SCREEN_WIDTH - (2 * SCREEN_MARGIN)) / MAXIMUM_CHARACTERS
COLORS = ['purple', 'blue', 'black']

velcro = Turtle()
screen = Screen()

def letter_A():
    velcro.left(90)
    velcro.forward(150)
    velcro.right(90)
    velcro.forward(150)
    velcro.right(90)
    velcro.forward(150)
    velcro.right(180)
    velcro.forward(75)
    velcro.left(90)
    velcro.forward(150)

# ...

def letter_Z():
    velcro.forward(225)
    velcro.left(140)
    velcro.forward(300)
    velcro.right(140)
    velcro.forward(225)

letter_lookup = {
    'A': letter_A,
    'B': letter_B,
    'C': letter_C,
    'D': letter_D,
    'E': letter_E,
    'F': letter_F,
    'G': letter_G,
    'H': letter_H,
    'I': letter_I,
    'J': letter_J,
    'K': letter_K,
    'L': letter_L,
    'M': letter_M,
    'N': letter_N,
    'O': letter_O,
    'P': letter_P,
    'Q': letter_Q,
    'R': letter_R,
    'S': letter_S,
    'T': letter_T,
    'U': letter_U,
    'V': letter_V,
    'W': letter_W,
    'X': letter_X,
    'Y': letter_Y,
    'Z': letter_Z,
}

screen.setup(width=SCREEN_WIDTH, height=SCREEN_HEIGHT)

screen.bgcolor('pink')
velcro.color("purple", "blue")
velcro.pensize("12")

color_string = ", ".join(COLORS[:-1]) + " or " + COLORS[-1]

velcroColor = screen.textinput("Pick a Color", "Please chose from the colors " + color_string + ", to draw with")

if (velcroColor in COLORS):
    velcro.color(velcroColor)

velcroLetters = screen.textinput("Turtle alphabet", "Please enter up to 3 letters from A-Z to draw:")[:MAXIMUM_CHARACTERS]

center_x = CHARACTER_WIDTH * (len(velcroLetters) - 1) / -2

for letter in velcroLetters:
    velcro.penup()
    velcro.home()
    velcro.goto(center_x, 0)
    velcro.pendown()
    letter_lookup[letter.upper()]()

    center_x += CHARACTER_WIDTH

screen.mainloop()

---

不确定发生了什么，

turtle.textinput（）

允许我输入任意数量的字母，甚至非字母字符。我可以输入任意数量的字母，turtle只是不画而已