def pop_counted(a):

    pop_counted.counter += 1

    return a.pop()

pop_counted.counter = 0

import collections

​

arr = ['a', 'a', 'b', 'b', 'b', 'c']

​

# set the elements frequencies using Counter class

elements_count = collections.Counter(arr)

​

# printing the element and the frequency

for key, value in elements_count.items():

    print(f"{key}: {value}")

​

# output

# a: 2

# b: 3

# c: 1

​

​

data = 'hello world'

​

# set the elements frequencies using Counter class

elements_count = collections.Counter(data)

​

# printing the element and the frequency

print(elements_count)

>>> from collections import Counter

>>> colors = ['blue', 'blue', 'blue', 'red', 'red']

>>> counter = Counter(colors)

>>> counter['yellow'] += 1

Counter({'blue': 3, 'red': 2, 'yellow': 1})

>>> counter.most_common()[0]

('blue', 3)

>>> # Tally occurrences of words in a list

>>> cnt = Counter()

>>> for word in ['red', 'blue', 'red', 'green', 'blue', 'blue']:

...     cnt[word] += 1

>>> cnt

Counter({'blue': 3, 'red': 2, 'green': 1})

​

>>> # Find the ten most common words in Hamlet

>>> import re

>>> words = re.findall(r'\w+', open('hamlet.txt').read().lower())

>>> Counter(words).most_common(10)

[('the', 1143), ('and', 966), ('to', 762), ('of', 669), ('i', 631),

 ('you', 554),  ('a', 546), ('my', 514), ('hamlet', 471), ('in', 451)]

>>> Counter('abracadabra').most_common(3)

[('a', 5), ('r', 2), ('b', 2)]

​

sum(c.values())                 # total of all counts

c.clear()                       # reset all counts

list(c)                         # list unique elements

set(c)                          # convert to a set

dict(c)                         # convert to a regular dictionary

c.items()                       # convert to a list of (elem, cnt) pairs

Counter(dict(list_of_pairs))    # convert from a list of (elem, cnt) pairs

c.most_common()[:-n-1:-1]       # n least common elements

c += Counter()                  # remove zero and negative counts

​

>>> from collections import Counter

​

>>> # Use a string as an argument

>>> Counter("mississippi")

Counter({'i': 4, 's': 4, 'p': 2, 'm': 1})

​

>>> # Use a list as an argument

>>> Counter(list("mississippi"))

Counter({'i': 4, 's': 4, 'p': 2, 'm': 1})

​

>>> # Use a dictionary or set as an argument

>>> Counter(i=4, s=4, p=2, m=1)

Counter({'i': 4, 's': 4, 'p': 2, 'm': 1})

>>> Counter(set("mississippi"))

Counter({'p': 1, 's': 1, 'm': 1, 'i': 1})

​

>>> # Use .update() to update object counts, use with both iterables and mappings

>>> letters = Counter({"i": 4, "s": 4, "p": 2, "m": 1})

>>> letters.update("missouri")

>>> letters

Counter({'i': 6, 's': 6, 'p': 2, 'm': 2, 'o': 1, 'u': 1, 'r': 1})

​

>>> # Accessing the counter's content

>>> letters = Counter("mississippi")

>>> letters["p"]

2

>>> for letter in letters:

...     print(letter, letters[letter])

...

m 1

i 4

s 4

p 2

​

>>> for letter in letters.keys():

...     print(letter, letters[letter])

...

m 1

i 4

s 4

p 2

​

>>> for count in letters.values():

...     print(count)

...

1

4

4

2

​

>>> for letter, count in letters.items():

...     print(letter, count)

...

m 1

i 4

s 4

p 2

​

​

>>> # Finding the most common objects

>>> sales = Counter(banana=15, tomato=4, apple=39, orange=30)

​

>>> # The most common object

>>> sales.most_common(1)

[('apple', 39)]

​

>>> # The two most common objects

>>> sales.most_common(2)

[('apple', 39), ('orange', 30)]

​

>>> # All objects sorted by count

>>> sales.most_common()

[('apple', 39), ('orange', 30), ('banana', 15), ('tomato', 4)]

​

>>> sales.most_common(None)

[('apple', 39), ('orange', 30), ('banana', 15), ('tomato', 4)]

import time

from time import sleep, time

​

can_run = True

the_number = 0

​

end_number = 11 #you can change the number to be last counted

​

while can_run:

    print(the_number)

    sleep(1)

    the_number = the_number + 1

    if  the_number == end_number: 

        can_run = False

>>> c = Counter(a=4, b=2, c=0, d=-2)

>>> d = Counter(a=1, b=2, c=3, d=4)

>>> c.subtract(d)

>>> c

Counter({'a': 3, 'b': 0, 'c': -3, 'd': -6})

​