Suppose a Python tuple TUP is declared as TUP=('A','B','C') Which of the…
2023
Suppose a Python tuple TUP is declared as TUP=('A','B','C') Which of the following command is invalid ?
- A.
TUP=('D')
- B.
TUP=('D',)
- C.
TUP+=('D')
- D.
TUP+=('D',)
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Correct answer: C
Answer: The invalid command is TUP+=('D').
Reason: ('D') is not a tuple but the string 'D'. Trying to concatenate a tuple and a string with += raises a TypeError: can only concatenate tuple (not "str") to tuple.
TUP=('D') — valid Python, but this assigns the string 'D' (not a tuple). Use a trailing comma to make a one-element tuple.
TUP=('D',) — valid: this is a one-element tuple containing 'D'.
TUP+=('D') — invalid: ('D') is a string, so tuple + string raises a TypeError.
TUP+=('D',) — valid: concatenates two tuples. Although tuples are immutable, += will rebind the name TUP to the new tuple result.
Tip: when creating a single-element tuple, always include the trailing comma: ('element',).