17条提高工作效率的Python技巧分享

# bad practice码 n1 = input("enter a number : ") n2 = input("enter a number : ") n2 = input("enter a number : ") print(n1, n2, n3)

# good practice n1, n2, n3 = input("enter a number : ").split() print(n1, n2, n3)

size = "lg" color = "blue" price = 50 # bad practice if size == "lg" and color == "blue" and price <100:   print("yes, i want to but the product.")< pre>

# good practice conditions = [     size == "lg",     color == "blue",     price <100, ] if all(conditions):     print("Yes, I want to but the product.")

# bad practice size = "lg" color = "blue" price = 50 if size == "lg" or color == "blue" or price <100:   print("yes, i want to but the product.")< pre>

# good practice conditions = [     size == "lg",     color == "blue",     price <100, ] if any(conditions):     print("Yes, I want to but the product.")

print('odd' if int(input('Enter a number: '))%2 else 'even')

v1 = 100 v2 = 200 # bad practice temp = v1 v1 = v2 v2 = temp

v1 = 100 v2 = 200 # good practice v1, v2 = v2, v1

print("John Deo"[::-1])

v1 = "madam" # is a palindrome string v2 = "master" # is not a palindrome string print(v1.find(v1[::-1]) == 0) # True print(v1.find(v2[::-1]) == 0) # False

name = "ali" age = 22 # bad practices if name:     print(name) if name and age > 18:     print("user is verified")

# a better approach print(name if name else "") """ here you have to define the else condition too""" # good practice  name and print(name) age > 18 and name and print("user is verified")

lst = [1, 2, 3, 4, 3, 4, 4, 5, 6, 3, 1, 6, 7, 9, 4, 0] print(lst) unique_lst = list(set(lst)) print(unique_lst)

lst = [1, 2, 3, 4, 3, 4, 4, 5, 6, 3, 1, 6, 7, 9, 4, 0] most_repeated_item = max(lst, key=lst.count) print(most_repeated_item)

numbers = [1,2,3,4,5,6,7] evens = [x for x in numbers if x % 2 is 0] odds = [y for y in numbers if y not in evens] cities = ['London', 'Dublin', 'Oslo'] def visit(city):     print("Welcome to "+city) for city in cities:     visit(city)

def sum_of_squares(n1, n2)     return n1**2 + n2**2 print(sum_of_squares(2,3)) # output: 13 """ what ever if you want to pass, multiple args to the function  as n number of args. so let's make it dynamic. """  def sum_of_squares(*args):     return sum([item**2 for item in args]) # now you can pass as many parameters as you want print(sum_of_squares(2, 3, 4)) print(sum_of_squares(2, 3, 4, 5, 6))

lst = ["blue", "lightblue", "pink", "orange", "red"] for idx, item in enumerate(lst):      print(idx, item)

names = ["john", "sara", "jim", "rock"] print(", ".join(names))

d1 = {"v1": 22, "v2": 33} d2 = {"v2": 44, "v3": 55} d3 = {**d1, **d2} print(d3)

keys = ['a', 'b', 'c'] vals = [1, 2, 3] zipped = dict(zip(keys, vals))

d = {     "v1": 80,     "v2": 20,     "v3": 40,     "v4": 20,     "v5": 10, } sorted_d = dict(sorted(d.items(), key=lambda item: item[1])) print(sorted_d)

from operator import itemgetter sorted_d = dict(sorted(d.items(), key=itemgetter(1)))

sorted_d = dict(sorted(d.items(), key=itemgetter(1), reverse=True))

from pprint import pprint data = {     "name": "john deo",     "age": "22",     "address": {"contry": "canada", "state": "an state of canada :)", "address": "street st.34 north 12"},     "attr": {"verified": True, "emialaddress": True}, } print(data) pprint(data)

{'name': 'john deo', 'age': '22', 'address': {'contry': 'canada', 'state': 'an state of canada :)', 'address': 'street st.34 north 12'}, 'attr': {'verified': True, 'emialaddress': True}} {'address': {'address': 'street st.34 north 12',              'contry': 'canada',              'state': 'an state of canada :)'},  'age': '22',  'attr': {'emialaddress': True, 'verified': True},  'name': 'john deo'}