python_基础知识
列表去重,如果不需要保留原有数据的顺序,可以直接使用集合去重就行,但如果需要保留原有顺序,可以按下方操作: a = ['9','2','3','4','4','4','4'] b = list(set(a)) # 将集合对象转回列表 b.sort(key=a.index) # 让b列表的排序按原有a的元索引值排序 print(b) # ['9', '2', '3', '4']
python时间
def which_month(last=None): # last=None 求上个月是哪年哪个月, last!=None 是上上个月 if last is None: last_month = yesterday()[:-2] else: month = datetime.datetime.strptime(yesterday(), "%Y%m%d").month if month == 1: year = datetime.datetime.strptime(yesterday(), "%Y%m%d").year year = year - 1 month = 12 last_month = str(year) + str(month) else: last_month = str(int(yesterday()[:-2]) - 1) return last_month def current_date(): return datetime.datetime.now().strftime('%Y%m%d') def today(): return datetime.datetime.now().strftime('%Y-%m-%d_%H:%M:%S') def yesterday(days=1): delta = datetime.timedelta(days=days) today_s = datetime.datetime.strptime(current_date(), "%Y%m%d") yesterday = (today_s - delta).strftime("%Y%m%d") return yesterday