Python Data Structures: Strings, Lists, Tuples, Dicts & Sets

1. Strings

Demonstrates creating a string variable and using common string methods such as capitalize(), count(), center(), endswith(), isdigit(), join(), strip(), split(), and formatted output with format().

name = 'derek'
print(name.capitalize())          # Derek
print(name.count("e"))            # 2
print(name.center(10, '*'))       # **derek***
print(name.endswith("k"))         # True
print('244'.isdigit())            # True
print('+'.join(['1','2','3']))   # 1+2+3
print('
123'.strip())           # 123
print("1+2+3+4".split("+"))      # ['1','2','3','4']
msg = 'my name is {name} and i am {age} old'
print(msg.format(name='derek', age=20))  # my name is derek and i am 20 old

Common built‑in string methods are listed with brief explanations:

# 1  string.capitalize()          # first character uppercase
# 2  string.center(width)         # center string, pad with spaces
# 3  string.count(sub, beg=0, end=len(string))  # count occurrences
# 4  string.decode(encoding='UTF-8', errors='strict')
# 5  string.encode(encoding='UTF-8', errors='strict')
# 6  string.endswith(suffix, beg=0, end=len(string))
# 7  string.expandtabs(tabsize=8)
# 8  string.find(sub, beg=0, end=len(string))
# 9  string.index(sub, beg=0, end=len(string))
#10  string.isalnum()
#11  string.isalpha()
#12  string.isdecimal()
#13  string.isdigit()
#14  string.islower()
#15  string.isnumeric()
#16  string.isspace()
#17  string.istitle()
#18  string.isupper()
#19  string.join(iterable)
#20  string.ljust(width)
#21  string.lower()
#22  string.lstrip()
#23  string.maketrans(intab, outtab)
#24  max(string)
#25  min(string)
#26  string.partition(sep)
#27  string.replace(old, new, num=string.count(old))
#28  string.rfind(sub, beg=0, end=len(string))
#29  string.rindex(sub, beg=0, end=len(string))
#30  string.rjust(width)
#31  string.rpartition(sep)
#32  string.rstrip()
#33  string.split(sep="", num=string.count(sep))
#34  string.splitlines(num=string.count('
'))
#35  string.startswith(prefix, beg=0, end=len(string))
#36  string.strip([chars])
#37  string.swapcase()
#38  string.title()
#39  string.translate(table, del="")
#40  string.upper()

2. Lists

Shows how to create a list, access elements by index or slice, and perform common operations such as append(), remove(), pop(), del, insert(), extend(), count(), sort(), reverse(), index(), and iteration with enumerate().

# create list
fruit = ['apple', 'pear', 'grape', 'orange']
print(fruit[1])          # pear
print(fruit[1:3])        # ['pear', 'grape']
print(fruit[-1])         # orange
print(fruit[:2])         # ['apple', 'pear']
# append
fruit.append('peach')
print(fruit)
# remove
fruit.remove('peach')
print(fruit)
# pop last element
fruit.pop()
print(fruit)
# delete by index
del fruit[2]
print(fruit)
# insert at index 1
fruit.insert(1, 'grape')
print(fruit)
# modify element
fruit[2] = 'orange'
print(fruit)
# extend with another list
fruit1 = ['apple', 'orange']
fruit2 = ['pear', 'grape']
fruit1.extend(fruit2)
print(fruit1)
# count occurrences
print(fruit1.count('apple'))
# sort and reverse
fruit1.sort()
print(fruit1)
fruit1.reverse()
print(fruit1)
# get index
print(fruit1.index('apple'))
# enumerate
for idx, item in enumerate(fruit1):
    print(idx, item)

3. Tuples

Illustrates tuple creation and two useful methods: count() and index().

fruit = ('apple', 'orange', 'grape')
print(fruit.count('apple'))   # 1
print(fruit.index('orange'))  # 1

4. Dictionaries

Demonstrates creating a dictionary, adding and modifying key‑value pairs, deleting entries with pop(), retrieving values with get(), and iterating over keys, values, or items.

# create
dict_fruit = {1: 'apple', 2: 'orange', 3: 'grape'}
print(dict_fruit)
# add
dict_fruit[4] = 'pear'
print(dict_fruit)
# modify
dict_fruit[4] = 'peach'
print(dict_fruit)
# delete
dict_fruit.pop(4)
print(dict_fruit)
# get value
print(dict_fruit.get(1))
# iterate
for k, v in dict_fruit.items():
    print(k, v)
for k in dict_fruit.keys():
    print(k)
for v in dict_fruit.values():
    print(v)

5. Sets

Shows how to create a set, add single or multiple elements, remove elements, and perform set operations such as union, difference, and intersection.

# create
fruit = set(['apple', 'orange', 'pear'])
print(fruit)
# add single element
fruit.add('grape')
print(fruit)
# add multiple elements
fruit.update(['peach', 'banana'])
print(fruit)
# remove specific element
fruit.remove('banana')
print(fruit)
# pop random element
fruit.pop()
print(fruit)
# set operations
num1 = set([11, 22, 33, 44])
num2 = set([33, 44, 55, 66])
print(num1.union(num2))        # {11, 22, 33, 44, 55, 66}
print(num1.difference(num2))   # {11, 22}
print(num1.intersection(num2)) # {33, 44}