# 第一种方式，如果传入字符串时间  
date1 = time.strptime('2018-08-16 01:28:33', "%Y-%m-%d %H:%M:%S")  
date2 = time.strptime('2018-10-18 06:26:54', "%Y-%m-%d %H:%M:%S")  
date1 = datetime.datetime(date1[0], date1[1], date1[2], date1[3], date1[4], date1[5])  # 转为日期类型  
date2 = datetime.datetime(date2[0], date2[1], date2[2], date2[3], date2[4], date2[5])  
print("类型{0},时间{1}".format(type(date1), date1))  
print("类型{0},时间{1}".format(type(date2), date2))  
print(date2-date1)  # 时间差  
date_del = date2 - date1  
all_seconds = date_del.days * 24 * 3600 + date_del.seconds  # 总秒数  
print(all_seconds)  

# 第二种方式，传入日期类型  
now = datetime.datetime.now()  
print(now)  
seven_days = datetime.datetime.now() + datetime.timedelta(days=7)  # 7天后  
print(seven_days)  
# 格式化日期  
x = (datetime.datetime.now() + datetime.timedelta(days=-1)).strftime('%Y/%m/%d %H:%M')  
y = (datetime.datetime.now() + datetime.timedelta(days=-1)).strftime('%Y-%m-%d %H:%M')  
print(type(x))  
print(x)  
print(y)  
# 日期时间差  
# 注意如果两个结果相减求秒数，结果不会将天也化为秒，只是以十分秒的形式相减  
time_minus = (seven_days - now).seconds  
print(time_minus)  # 结果为0  
time_minus_day = (seven_days - now).days  
print(time_minus_day)  # 结果为7  

结果图片: