Identifiers in Python

1. Which character set does Python recognize for its identifiers?

ASCII only
Unicode
EBCDIC

Python uses Unicode, supporting a vast range of international characters.

2. An identifier cannot start with which of the following?

An underscore (_)
A letter (A-Z or a-z)
A digit (0-9)

Rules state: Identifiers must start with a letter or underscore, never a number.

3. How does Python treat identifiers ‘Value’ and ‘value’?

As identical
As different (Case Sensitive)
Only ‘value’ is valid

Python is case-sensitive; uppercase and lowercase versions are distinct names.

4. Which of these symbols is allowed inside an identifier?

Hyphen (-)
Underscore (_)
Dollar Sign ($)

Only letters, digits, and underscores are allowed.

5. What is the limit on the length of a Python identifier?

31 Characters
255 Characters
Unlimited length

Python identifiers can be of any length.

6. Can a ‘Keyword’ like ‘while’ be used as a variable name?

Yes, always
No, they are reserved
Yes, if in uppercase

Keywords are reserved words and cannot be used as identifiers.

7. Are spaces allowed inside a single identifier name?

No
Yes, if quoted

Identifiers must be a single continuous word. Spaces are delimiters.

8. Which of these can be an identifier?

Variable names only
Variable, Function, and Class names
Literals

Identifier is a general term for user-defined names in a program.

9. What category do symbols like [], {}, and () fall into?

Identifiers
Punctuators
Literals

They are punctuators/delimiters and cannot be part of an identifier name.

10. Why is starting with a digit illegal?

It uses more RAM
To prevent confusion with numeric literals

The interpreter needs to know immediately if it’s reading a number or a name.

11. Which of these is a VALID identifier?

2nd_var
_total_score
total-score

_total_score is valid. A cannot start with digit; C cannot use hyphen.

12. Identify the INVALID identifier:

True_Val
True
TRUE

‘True’ is a reserved keyword/literal and cannot be a variable name.

13. Which of the following is invalid because of a punctuator?

roll_no
roll.no
rollNo

The dot (.) is a punctuator used for object access and is illegal in a name.

14. Is ‘____’ (multiple underscores) a valid identifier?

Yes
No

Yes, identifiers can consist entirely of underscores.

15. Identify the VALID identifier:

my$price
data_2
class

‘data_2’ is valid. ‘class’ is a keyword; ‘$’ is an illegal symbol.

16. Which of these is invalid due to naming rules?

else
Else
ELSE

‘else’ (all lowercase) is a reserved keyword. Others are valid identifiers.

17. Which identifier is correctly formed?

student name
_student_name
student@name

Underscores are the only special characters allowed.

18. Identify the valid identifier using digits:

9lives
lives9
lives-9

‘lives9’ is valid because the digit is not at the start.

19. Which of these can be used as a name?

yield
yield_value

‘yield’ is a keyword; ‘yield_value’ is a user-defined name and is valid.

20. What is the output of choosing ‘None’ as a variable name?

Success
SyntaxError

‘None’ is a reserved special literal/keyword.

Identifiers in Python

Python Identifiers Quiz

Part 1: Theoretical Rules

Part 2: Examples & Validation