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Write a function that takes a positive integer, i and returns a dictionary that maps integers from 1 to i. Each integer is going to map itself. Example:

>>> create_dict(3)
{1: 1, 2: 2, 3: 3}
>>> create_dict(1)
{1: 1}

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Write a function that takes a list and returns a new list which is reverse of the input list.
>>> a = [4, 3, 1, 2]
>>> d = reverse_list(a)
[2, 1, 3, 4]

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Write a function that takes two dictionaries and counts how many key-value pairs are exactly the same in both dictionaries. Only count pairs where the key and the value are the same in both.. Example:

>>> d1 = {'a': 1, 'b': 2, 'c': 3}
>>> d2 = {'a': 1, 'b': 3, 'c': 3, 'd': 1}
>>> count_common_pairs(d1, d2)
2

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Write a function that takes a list and two integers, t, i and j changes t elements from index i to index j (including i not including j) with None

>>> a = [4, 3, 1, 2, 'ani', 'po']
>>> change_list(a, 1, 4)
>>> a
[4, None, None, None, 'ani', 'po']

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Write a function that takes a dictionary, d, whose keys are numbers and values are strings and returns a new dictionary by adding 2 to each key and '!' to each value. Example:

>>> add_to_dict({1: 'a', 4: 'jo be'})
{3: 'a!', 6: 'jo be!'}

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Write a function that takes a list of strings and a character, t and char and returns count of strings which start with char (case insensitive).

>>> startswith_count(['A', 'a', 'bs', 'Ne', 'Aron'], 'a')
3
>>> count = startswith_count(['A', 'Barber', 'Bask', 'bs', 'Ne', 'BS', 'BS'], 'B')
>>> count
5

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def dosmth(s, chars):
    res = ""
    for letter in s:
        if letter in chars:
            res = res + letter
    return len(res)

Given the above script, what are the results of the following expressions:

dosmth('python programming', 'pom'):
dosmth('python programming', 'arr'):

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def dosmth(s, i):
    index = 0
    while index < len(s):
        if index == i:
            return s[i]
        index = index + 1

Given the above script, what are the results of the following expressions:

dosmth('ani', 2):
dosmth('pse', 1):
dosmth('po', 5):

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Complete execution flow of the following program

Misses: 0

def add_number(d, n):
    for key in d:
        d[key] = d[key] + n

nums = {'a': 1, 2: 4}
nums = add_number(nums, -4)

Complete execution flow of the following program

Misses: 0

def histogram(s):
    d = {}
    for c in s:
        d[c] = d.get(c, 0) + 1
    return d

h = histogram('oob')