Theset.remove()method of Python will remove a particular element from the set. This method takes the single element you wanted to remove from the set as an argument, if the specified element does not exist in the set, then “KeyError” is returned. To overcome the error either you can u...
Python offers a straightforward approach that involves iterating over each item in the list and checking for a match to find if an element exists in the list using a loop. This method is particularly useful when you need to perform additional operations on matching elements or when working ...
(fname, 'r') as item: for line in item: token = line.strip('[\r\n]') token = token.split() if token[0] == esn: return token[2] return None logging.info('Set the next stack member ID, filename %s', file_path) uri = "/stack/stackMemberInfos/stackMemberInfo" str_temp = ...
在交互式环境中输入以下代码：if os.path.exists(‘/tmp/dest_backup’)==False:shutil.copytree(‘....
if os.path.exists('example.txt'): print("文件存在") else: print("文件不存在") 1. 2. 3. 4. 5. 6. 2. 重命名与删除文件 import os # 重命名文件 os.rename('old_name.txt', 'new_name.txt') # 删除文件 os.remove('file_to_delete.txt') ...
tasks = threadpool.makeRequests(outdata, datalist) # 规定线程执行的任务 # outdata是函数名,datalist是一个参数列表,线程池会依次提取datalist中的参数引入到函数中来执行函数,所以参数列表的长度也就是线程池所要执行的任务数量。 [pool.putRequest(req) for req in tasks] # 将将要执行的任务放入线程池中...
print 'I bought the', olditem print 'My shopping list is now', shoplist print语句的结尾使用了一个 逗号 来消除每个print语句自动打印的换行符 sort方法来对列表排序。需要理解的是,这个方法影响列表本身,而不是返回一个修改后的列表 del语句为我们从列表中删除它。我们指明我们想要删除列表中的第一个元素,...
list.remove(obj):移除列表中某个值的第一个匹配项,与pop区别是,删除的元素不会打印 test_ls = [1, 1, 1, 1, 2, 2, 2, 2, 3, 4, 5, 6, 7, 7, 8, 9, 10] print(f"原列表: {test_ls}") test_ls.remove(2) print(f"移除第一次遇到2元素后的列表: {test_ls}")输出结果 list.ex...
#import my_model#print(my_model.name)#my_model.my_func()frommy_modelimportname as XXX (二)第三方模块安装 1、if __name__ == '__main__' 判断 (1)if __name__ == '__main__' 判断:在当前文件内执行不起作用 #if __name__ == '__main__': # 输入main提示打印出来deffunc():prin...
if a == 1: print("1") elif a == 2: print("2") elif a == 3: print("3") else: print("???") 异常处理 简单的异常处理如下,首先执行try中的语句,如果中途报错则执行except中的指令,否则不执行。 try: num = eval(input("请输入一个整数:")) print...