Introduction to Tuple and List and Dictionary in Python. Try to demonstrate useful concepts with making question marks in the reader's head!

1. Welcome to Python
Tuple, List, Dictionary

2. Gimme a definition! → Tuple
• Tuple is one of python data types that categorize
as sequence and it consists of comma-
separated objects like string, number, list and
even another tuple!
• Tuple is immutable, and that’s differ it from list
• Immutable: An object with a fixed value.
Immutable objects include numbers, strings and
tuples. Such an object cannot be altered. A new
object has to be created if a different value has to
be stored. They play an important role in places
where a constant hash value is needed, for
example as a key in a dictionary.(from
docs.python.org)

3. Examples for Tuple
Try it out !
1 >>> x = ("1", 2, [3])
>>> print(x)
????
>>> type(x)
????
2 >>> a = "1"
>>> b = 2
>>> c = [3]
>>> y = a, b, c
>>> print(y)
????
>>> type(y)
????
3 >>> a = "1"
>>> y = (a)
>>> type(y)
????
>>> a = "1"
>>> y = (a,)
>>> type(y)
????
>>> print(y)
????
>>> print(y[1])
????
>>> len(y)
????

4. Tuple: Advantages???
• tuple can assigned faster than list. Can you prove it by yourself? (Try to compare with list creation code!)
• Write protected!
• Use less memory than list. Because, tuple is fixed-size and list is variable-sized.
• Can assign as key at dictionary

5. Tuple: Operations
1. Accessing Values :
• x = (1, 2, 3, 4, 5)
• x[0]
• x[len(x)-1] # or ?
2. Concatenation :
• a = (1, 2, 3)
• b = (4, 5, 6)
• c = a + b
3. Multiply :
• x = ("A",)
• x = x * 2 #??
4. Delete Tuple :
• del x[0] #??
• del x # ??
5. Comparison :
• print((1, 2) == (1, 2))
• print((1, 2) is (1, 2))
 The == operator compares the values of both
the operands and checks for value equality.
Whereas is operator checks whether both the
operands refer to the same object or not.
• x = (1, 2)
• y = x
• print(x is y and x == y) #??
6. The ‘in’ operator:
• x = (1, 2)
• print(1 in x)
• print((1 and 2) in x) # print((1 or 4) in x)
7. ‘sorted’ function with ‘reverse’ parameter

6. One question?
>>> x = ("1", 2, [3])
>>> print(x)
>>> y = x[2]
>>> y.append(4)
>>> y.append(5)
>>> y.append(6)
>>> print(x)

7. List = Tuple + something
Additional to tuples:
• sort:
• x=[5,6,2,3,5]
• x.sort()
• reserve:
• x.reverse()
• copy:
• x = [1,3,6]
• y=x
• z=x.copy()
• y[1] = 888
• print(x[1]) #???
• print(z[1]) #???
• List as stack:
• append() and pop()
• del stands for delete
 What is lambda?
 What is list comprehension?!

8. Dictionary, Are you looking up for something?
• Dictionary consists of two main part:
• Key: What is you will save and retrieve
value with
• Value: What you want to hide with Key
• Why we used hide in above sentences?
• For creating dictionary just use this pattern:
• ‘[key]’:[value] like bellow:
• d = {‘name’:’some thing’,’age’:150}
• How to get ‘some thing’ back??
• d[0] or d[‘name’] or …
• There is no order in saving values for keys
(unlike list)
• Can we say list is a dictionary with ordered
integer as key?
• There is another way to build dictionary
with dict() constructor:
• dict([('sape', 4139), ('guido', 4127), ('jack',
4098)])

9. Dictionary
• Looping through dictionary elements:
• knights = {'gallahad': 'the pure', 'robin':
'the brave'}
• for k, v in knights.items():#(key,value)
• for v in knights.values():
• for k in knights.keys():
• zip:
• For making dictionary out of 2 list with
same size:
• questions = ['name', 'quest', 'favorite
color']
• answers = ['lancelot', 'the holy grail',
'blue']
• for a,b in zip(questions,answers):
• print("%s = %s" % (a,b))
• enumerate: (a way to make list!)
• for i, v in enumerate([‘ali’,’jack’]:

10. Link to source
https://docs.python.org/3/tutorial/datastructures.html
https://www.w3schools.com/python/