Understanding Python Variables

What are the main types of variables in Python?

• int, float, str, list, tuple, dict, set

• float, double, list

• string, number, object

• boolean, character, array

Explain the difference between local and global variables.

• Local variables can be accessed globally if declared first.

• Global variables are only accessible within functions.

• Local variables retain their values even after the function ends.

• Local variables are accessible only within their defined scope, while global variables are accessible throughout the entire program.

What is the scope of a variable?

• The scope of a variable is the time duration for which the variable exists.

• The scope of a variable is the data type of the variable.

• The scope of a variable is the region of the program where the variable is defined and can be accessed.

• The scope of a variable is the memory location where the variable is stored.

What are mutable and immutable variables?

• Mutable variables cannot be changed; immutable variables can be changed after creation.

• Both mutable and immutable variables can be changed at any time.

• Mutable variables are always faster than immutable variables.

• Mutable variables can be changed; immutable variables cannot be changed after creation.

Give an example of a valid variable name in Python.

• my-variable

• 1st_variable

• myVariable

• my_variable

What is the purpose of variable naming conventions?

• To ensure all variables are declared as constants.

• To limit the number of variables in a program.

• To improve code readability and maintainability.

• To increase the execution speed of the code.

How do you convert a string to an integer in Python?

• Apply float(string) to convert a string to a float.

• Use eval(string) to evaluate the string as an expression.

• Use str(int) to convert an integer to a string.

• Use int(string) to convert a string to an integer.

What happens to a variable's scope when defined inside a function?

• The variable's scope becomes local to the function.

• The variable's scope becomes global to the program.

• The variable is automatically deleted after the function ends.

• The variable can be accessed from any other function.

Can you change the value of an immutable variable? Why or why not?

• No, you cannot change the value of an immutable variable.

• You can change the value by using a different variable name.

• Immutable variables can be reassigned under certain conditions.

• Yes, you can change the value of an immutable variable.

What is the difference between a list and a tuple in terms of mutability?

• Lists are mutable; tuples are immutable.

• Tuples can be changed after creation; lists cannot.

• Both lists and tuples are mutable.

• Lists are immutable; tuples are mutable.