python question-answer

Best way to read file:

with open(file_name) as fp:
    fp.read()


write lines to file
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with open(file_name, 'w') as fp:
    fp.writelines(text)


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Get prime numbers:

nums = range(2, 50)
for i in range(2, 8):
    nums = filter(lambda x: x == i or x % i, nums)

print nums


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Remove duplicates from a list: [use one line command 'set': this removes duplicates: it may sort also but no guarantee of ordering: to sort use 'sorted']

a = [8,8,9,10]
b = set(a)
print b
=> [8,9,10]

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