Dynamic typing in Python - Step-by-Step Execution

Concept Flow - Dynamic typing in Python

Assign value to variable

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Python stores value with type

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Variable can be reassigned

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New value can be different type

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Python updates variable's type dynamically

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Use variable with new type

Python lets you assign any type of value to a variable and change it later without errors.

Execution Sample

Python

x = 10
print(type(x))
x = 'hello'
print(type(x))

Assign an integer to x, print its type, then assign a string to x and print its new type.

Execution Table

Step	Code executed	Variable 'x' value	Type of 'x'	Output
1	x = 10	10	int
2	print(type(x))	10	int	<class 'int'>
3	x = 'hello'	'hello'	str
4	print(type(x))	'hello'	str	<class 'str'>
5	End of code	'hello'	str	Execution stops

💡 Code ends after printing the type of x as str.

Variable Tracker

Variable	Start	After Step 1	After Step 3	Final
x	undefined	10 (int)	'hello' (str)	'hello' (str)

Key Moments - 2 Insights

Why can the variable 'x' hold both an integer and a string?

Because Python uses dynamic typing, it allows variables to change type when reassigned, as shown in steps 1 and 3 of the execution_table.

Does Python require declaring the type of a variable before assigning a value?

No, Python figures out the type automatically when you assign a value, as seen in step 1 where 'x' is assigned 10 without type declaration.

Visual Quiz - 3 Questions

Look at the execution_table at step 2, what is the output?

A <class 'int'>

B <class 'str'>

C 10

D hello

💡 Hint

Check the Output column at step 2 in the execution_table.

At which step does the variable 'x' change its type?

A Step 1

B Step 3

C Step 2

D Step 4

💡 Hint

Look at the 'Type of x' column in the execution_table between steps 2 and 3.

If we assign x = 3.14 after step 3, what would be the type of 'x'?

A int

B str

C float

D bool

💡 Hint

Remember Python updates the variable's type dynamically as shown in the variable_tracker.

Concept Snapshot

Dynamic typing means variables can hold any type and change types anytime.
No need to declare types before use.
Python tracks the type of the value stored in the variable.
Reassigning a variable updates its type automatically.
Use type() to check the current type of a variable.

Full Transcript

This example shows how Python variables can hold different types of values at different times. Initially, x is assigned the integer 10, so its type is int. Then x is reassigned the string 'hello', changing its type to str. Python does not require declaring variable types; it figures out the type from the assigned value. This flexibility is called dynamic typing. You can check the type of any variable using the type() function. The execution table traces each step, showing how the value and type of x change. This helps beginners understand how Python handles variable types dynamically.