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bundle exec jekyll serve

zhoudaxia233

字符串不存在原地反转这种操作，因为字符串是不可变的！！！ list是可变的，所以list可以原地反转。

# a is a list
a[:] = a[::-1]

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import os
here = os.path.dirname(os.path.abspath(__file__))

参考：
https://stackoverflow.com/questions/21957131/python-not-finding-file-in-the-same-directory https://stackoverflow.com/questions/1315390/python-find-a-file-in-the-same-directory

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lst = [[0, 1], [0, 4], [1, 0], [4, 0]]
data = {tuple(item) for item in map(sorted, lst)}     # method 1
data = {tuple(sorted(item)) for item in lst}          # method 2

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Type 1:

from itertools import tee
def pairwise(iterable):
    "s -> (s0,s1), (s1,s2), (s2, s3), ..."
    a, b = tee(iterable)
    next(b, None)
    return zip(a, b)

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sudo python3.6 -m pip install --upgrade pip
sudo python3.6 -m pip install [package_name]

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sudo add-apt-repository ppa:jonathonf/python-3.6
sudo apt update
sudo apt install python3.6

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Removal of Tuple Parameter Unpacking

zs = [(1, 10), (2, 20), (3, 30), (4, 40), (5, 50)]
# t1 = map(lambda (x, y): x+y, zs)  # python2 only
t1 = map(lambda tup: tup[0]+tup[1], zs)  # python2 & python3 
t2 = list(t1)
print(t2)


# def fxn(a, b_c, d): # b_c is (b,c) 2to3 refactoring tool

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flatten = lambda x: [y for l in x for y in flatten(l)] if type(x) is list else [x]

# Below is for you to understand 
# flatten = lambda x: [item for items in itemss for item in flatten(items)] if type(itemss) is list else [itemss]

>>> a = [1, 2, [3, 4], [[5, 6], [7, 8]]]
>>> flatten(a)
[1,2,3,4,5,6,7,8]

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from collections import Counter

l1 = "I have a dog and a cat sally."
l2 = "Why the fuck I have a dog and a cat cat."

# should output "5：why the fuck cat sally"

l1 = l1.split()
l2 = l2.split()