Task08：模块与datetime模块

练习题：

1、怎么查出通过 from xx import xx导⼊的可以直接调⽤的⽅法？

​ 在test_package文件夹中创建一个 init.py 的模块文件，内容可以为空。然后在代码中把test_package的文件的路径加入到python解释器可以搜索到的路径列表中。

2、了解Collection模块，编写程序以查询给定列表中最常见的元素。

题目说明：

输入：language = [‘PHP’, ‘PHP’, ‘Python’, ‘PHP’, ‘Python’, ‘JS’, ‘Python’, ‘Python’,‘PHP’, ‘Python’]

输出：Python

"""
Input file
language = ['PHP', 'PHP', 'Python', 'PHP', 'Python', 'JS', 'Python', 'Python','PHP', 'Python']
   
Output file
Python
"""
def most_element(language):
    """ Return a list of lines after inserting a word in a specific line. """
   
    # your code here
    模块：
# collections.py
def most_element(language):
    a=0
    b=0
    for i in range(len(language)):
        for j in range(len(language)-1):
            if language[i]==language[j+1]:
                a=a+1
        if a>b:
            b=a
            cc=language[i]
    return cc
    
import collections
language = ['PHP', 'PHP', 'Python', 'PHP', 'Python', 'JS', 'Python', 'Python','PHP', 'Python']
print(collections.most_element(language))

练习题：

1、假设你获取了用户输入的日期和时间如2020-1-21 9:01:30，以及一个时区信息如UTC+5:00，均是str，请编写一个函数将其转换为timestamp：

题目说明:

"""
   
Input file
example1: dt_str='2020-6-1 08:10:30', tz_str='UTC+7:00'
example2: dt_str='2020-5-31 16:10:30', tz_str='UTC-09:00'
   
Output file
result1: 1590973830.0
result2: 1590973830.0
"""
   
   
import datetime
import re
from dateutil import parser  
 
dt_str=‘2020-6-1 08:10:30’
tz_str=‘UTC+7:00’
  
def to_timestamp(dt_str, tz_str):
    # your code here
    dt = parser.parse(dt_str)
    tz_r = re.match(r’^UTC([+|-]\d{1,2}):00$’, tz_str)
    tz = datetime.timezone(datetime.timedelta(hours=int(tz_r.group(1))))
    dt = dt.replace(tzinfo=tz)
    return dt.timestamp()
        pass

2、编写Python程序以选择指定年份的所有星期日。

题目说明:

"""
   
Input file
   2020
   
Output file
   2020-01-05                         
   2020-01-12              
   2020-01-19                
   2020-01-26               
   2020-02-02     
   -----
   2020-12-06               
   2020-12-13                
   2020-12-20                
   2020-12-27 
"""
   
from datetime import date, timedelta   
def all_sundays(year):
    # your code here
    d = date(year, 1, 1) # January 1st
    d += timedelta(days = 6 - d.weekday()) # First Sunday
    while d.year == year:
       yield d
       d += timedelta(days = 7)
for d in allsundays(2020):
    print(d)