python函数模块导入使用问题，为什么会提示这个错误

Question

模块名：printing_functions.py

def print_models(unprinted_designs,completed_models):
    """
    模拟打印每个设计，直到没有未打印的设计为止。
    打印每个设计后，都将其移到列表completed_models中。
    """
    while unprinted_designs:
        current_design = unprinted_designs.pop()
        print(f"Printing model:{current_design}")
        completed_models.append(current_design)

def show_completed_models(completed_models):
    """显示打印好的所有模型"""
    print("\nThe folloeing models have been printed:")
    for completed_model in completed_models:
        print(completed_model)

导入模块

from printing_functions import print_models,show_completed_models

unprinted_designs = ['phone case','robot pendant','dodecahedron']
show_completed_models = []
    
printing_functions.print_models(unprinted_designs,completed_models)
printing_functions.show_completed_models(completed_models)

提示错误如下：
Traceback (most recent call last):
File "E:\python_work\8_15.py", line 6, in
printing_functions.print_models(unprinted_designs,completed_models)
NameError: name 'printing_functions' is not defined
[Finished in 122ms]

Answer 1

按你用法， 要这样import 
import printing_functions 

如果要这样import
from printing_functions import print_models,show_completed_models

那要这样用
print_models(unprinted_designs,completed_models)
show_completed_models(completed_models)