That happens when you call a function that returns a value in the Python Interactive Shell, but does not assign the return value to a variable?

a$.$ A SyntaxError is raised since the return value must be assigned to a variable.

$>>>$ sum $([6,7])$

Syntax Error: invalid syntax

$>$

$q,$

b$.$ The return value is printed as output.

$>>>{\displaystyle \underset{?}{\overset{?}{}}}([1,2])$

$3$

$>>>$

c$.$ The return value is saved in the variable.

$>>>{\displaystyle \underset{?}{\overset{?}{}}}([0,3])$

$>>>$ temp

$3$

$>>$

d$.$ No output is printed, except for a prompt, for the next command.

$>>>{\displaystyle \underset{?}{\overset{?}{}}}([4,5])$

$>>>$

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