gennad

#First year programmer, Python
def Factorial(x):
    res = 1
    for i in xrange(2, x + 1):
        res *= i
    return res
print Factorial(6)


#Lazy Python programmer

gennad

"""
A staticmethod is a method that knows
nothing about the class or instance it was
called on. It just gets the arguments that were
passed, no implicit first argument. It is
basically useless in Python -- you can just
use a module function instead of a
staticmethod.

A classmethod, on the other hand, is a

gennad

mylist = [x*x for x in range(3)]
for i in mylist :
    print(i)

# Generators can be read only once
mygenerator = (x*x for x in range(3))
for i in mygenerator :
   print(i)

Yield is a keyword that is used like return, except the function will return a generator.

gennad

import logging
logging.basicConfig(filename='example.log', level=logging.DEBUG)
logger = logging.getLogger(__name__)
logger.setLevel(logging.DEBUG)

# create console handler and set level to debug
ch = logging.StreamHandler()
ch.setLevel(logging.DEBUG)

# create formatter

gennad

class Singleton(type):
    def __init__(cls, name, bases, dict):
        super(Singleton, cls).__init__(name, bases, dict)
        cls.instance = None
    def __call__(cls,*args,**kw):
        if cls.instance is None:
            cls.instance = super(Singleton, cls).__call__(*args, **kw)
        return cls.instance

class MyClass(object):

gennad

#-*- coding: utf-8 -*-

"""
Написать функцию-фабрику, которая будет возвращать функцию сложения с аргументом.

>>> add5 = addition(5) # функция addition возвращает функцию сложения с 5
>>> add5(3) # вернет 3 + 5 = 8
8
>>> add5(8) # вернет 8 + 5 = 13
13

gennad

def make_hook(f):
    """Decorator to turn 'foo' method into '__foo__'"""
    f.is_hook = 1
    return f

class MyType(type):
    def __new__(cls, name, bases, attrs):

        if name.startswith('None'):
            return None

gennad

class myDecorator(object):

    def __init__(self, f):
        print "inside myDecorator.__init__()"
        f() # Prove that function definition has completed

    def __call__(self):
        print "inside myDecorator.__call__()"

@myDecorator

gennad

#Merges two sorted lists into one sorted list. recursively
def merge(left, right):
    if len(left) == 0 and len(right) == 0:
        return []
    elif len(left) == 0:
        return right
    elif len(right) == 0:
        return left
    else:
        if left[0] <= right[0]:

gennad

#Three-way QuickSort in Python
def quicksort(a):
    if len(a) == 0:
        return []
    p = a[(len(a)-1)//2]
    less = quicksort([x for x in a if x < p])
    greater = quicksort([x for x in a if x > p])
    equal = [x for x in a if x == p]
    return less + equal + greater