Page 190 - AI_Ver_3.0_class_11
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The following line would generate an error
                   city[1] = "New York"
              A tuple cannot be edited, But, a new tuple can be created by using an existing tuple (city) and a new value (New York).
                   city2 = city + ("New York",)   #comma indicates that it is a tuple

                   print(city2)  # Output: city = ("Delhi", "Madrid", "Chennai", "Rome", "New York")

                       Operations on Dictionary


              A dictionary is a collection of key-value pairs. Dictionaries are defined by enclosing elements in curly braces { }.

              Creating a Dictionary
              A dictionary can be created by enclosing key-value pairs in curly braces {}, with each pair separated by commas. Within
              each pair, the key and value are divided by a colon “:”

                   # Creating a dictionary
                   car = {
                       "make": "Toyota",
                       "model": "Camry",
                       "year": 2021,
                       "colour": "Blue"
                   }
              You can access the values in a dictionary by using the keys as shown:

                   print(car) # Output: {'make': 'Toyota', 'model': 'Camry', 'year': 2021, 'colour':
                   'Blue'}
                   print(car["make"])  # Output: Toyota
                   print(car["year"])   # Output: 2021

              Mutability
              In dictionaries, keys are immutable whereas values are mutable. You can change the values using the respective keys:

                   car["colour"]="Grey"
                   print(car)   #Ouput: {'make': 'Toyota', 'model': 'Camry', 'year': 2021, 'colour': 'Grey'}
              You can also add key-value pairs in an existing dictionary:

                   car["mileage"] = 15000
                   print (car)  #Ouput: {'make': 'Toyota', 'model': 'Camry', 'year': 2021, 'colour':
                   'Grey', 'mileage': 15000}
                       Control Statements


              Control statements in programming languages are essential tools that allow developers to dictate the flow of execution
              within their code. Depending on how the statements in a program will be executed, the flow of control in a program can
              be broadly classified into three types:
               • •  Sequence Statements
               • •  Conditional Statements
               • •  Iterative Statements

              Sequence Statement
              In Python, a sequence statement refers to a set of instructions that are executed in the order they appear. This is the most
              straightforward form of control flow.

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