The Python collection module is defined as a container that is used to store collections of data, for example, list, dict, set, and tuple, etc. It was introduced to improve the functionalities of the built-in collection containers.
Python collection module was first introduced in its 2.4 release.
There are different types of collection modules which are as follows:
The python namedtuple() function returns a tuple-like object with names for each position in the tuple. It was used to eliminate the problem of remembering the index of each field of a tuple object in ordinary tuples.
pranshu = ('Pranshu', 24, 'M')
print(pranshu)The Python OrderedDict() is similar to a dictionary object where keys maintain the order of insertion. If we try to insert key again, the previous value will be overwritten for that key.
import collections
d1=collections.OrderedDict()
d1['A']=10
d1['C']=12
d1['B']=11
d1['D']=13
for k,v in d1.items():
print (k,v)The Python defaultdict() is defined as a dictionary-like object. It is a subclass of the built-in dict class. It provides all methods provided by dictionary but takes the first argument as a default data type.
from collections import defaultdict number = defaultdict(int) number['one'] = 1 number['two'] = 2 print(number['three'])
The Python Counter is a subclass of dictionary object which helps to count hashable objects.
from collections import Counter
c = Counter()
list = [1,2,3,4,5,7,8,5,9,6,10]
Counter(list)
Counter({1:5,2:4})
list = [1,2,4,7,5,1,6,7,6,9,1]
c = Counter(list)
print(c[1])The Python deque() is a double-ended queue which allows us to add and remove elements from both the ends.
from collections import deque list = ["x","y","z"] deq = deque(list) print(deq)
