如果 else 语句附加到 for 循环中的列表

我想将海龟“person”添加到列表“infected_people”中，但出现错误“TurtleGraphicsError: bad color string: red”。

如何将“人”添加到“infected_people”列表中而不会出错。

我是编程新手，如果我的解释不清楚，我很抱歉。

infected_people = []

i = 0
while i < 30: #number of steps (time)
  for person in people: 
      random_walk(30, 400)
      i + 1
      for infected_person in infected_people: 
          if person.distance(infected_person) < 30: 
              person.color("red")
              infected_people.append(person) 

这是我代码的另一部分：

import turtle
import random

wn = turtle.Screen()

def person_characteristics(): 
    for person in people:
        person.penup()
        person.shape("circle")
        person.shapesize(0.2)
        x = random.randint(-200, 200)
        y = random.randint(-200, 200)
        person.setpos(x, y)
        person.speed(0)
        turtle.update()
    return person


def population(population_size):
    turtle.update()
    people = []
    for _ in range(population_size):
        people.append(turtle.Turtle())
    return people

def person_characteristics(): 
    for person in people:
        turtle.update()
        person.penup()
        person.shape("circle")
        person.shapesize(0.2)
        person.speed(0)
        x = random.randint(-200, 200)
        y = random.randint(-200, 200)
        person.setpos(x, y)
    return person

def random_walk(step_size, area_size):
    person.clear()
    count = 0
    while count < 1:
        count += 1
        if (-area_size < person.xcor() <area_size) and (-area_size < person.ycor() <area_size):
            person.right(random.randint(0,360))
            person.forward(step_size)
        else:
            person.right(180)
            person.forward(step_size)
    turtle.update()

people = population(50)
person = person_characteristics()

def infect_random(people):
    infected = random.choice(people)
    infected.color("red")
    return infected

infected_people = []
initial_infected = infect_random(people)
infected_people.append(initial_infected)
print(infected_people)
counted_infections = 0

我的目标是每个被感染的人（= 红点）都会感染其他靠近他的人。现在只有最初的感染者会感染其他人。所以我想如果我把每个被感染的人都添加到infected_people的列表中，那么它会起作用。但是，当添加行受感染_people.append(person) 时，我收到一个错误。

i = 0
while i < 30: #number of steps (time)
    for person in people: 
        random_walk(30, 400)
        i += 1
        for infected_person in infected_people: 
            if person.distance(infected_person) < 30: 
                person.color("red")
                infected_people.append(person)



turtle.done()
wn.exitonclick()

这是我得到的错误：

runfile('C:/Users/Noa Hoogeweg/Documents/BMT/PvL/Virus/Noa_Virus_goed.py', wdir='C:/Users/Noa Hoogeweg/Documents/BMT/PvL/Virus')
[<turtle.Turtle object at 0x000001FF4D3D9908>]
Traceback (most recent call last):

  File "C:\Users\Noa Hoogeweg\Documents\BMT\PvL\Virus\Noa_Virus_goed.py", line 78, in <module>
    person.color("red")

  File "C:\Users\Noa Hoogeweg\anaconda3\lib\turtle.py", line 2216, in color
    pcolor = self._colorstr(pcolor)

  File "C:\Users\Noa Hoogeweg\anaconda3\lib\turtle.py", line 2696, in _colorstr
    return self.screen._colorstr(args)

  File "C:\Users\Noa Hoogeweg\anaconda3\lib\turtle.py", line 1158, in _colorstr
    raise TurtleGraphicsError("bad color string: %s" % str(color))

TurtleGraphicsError: bad color string: red