I hope to provide more background knowledge here.
First, constructor signature of the of method threading::Thread:
class threading.Thread(group=None, target=None, name=None, args=(), kwargs={}, *, daemon=None)
args is the argument tuple for the target invocation. Defaults to ().
Second, A quirk in Python about tuple
:
Empty tuples are constructed by an empty pair of parentheses; a tuple with one item is constructed by following a value with a comma (it is not sufficient to enclose a single value in parentheses).
On the other hand, a string is a sequence of characters, like 'abc'[1] == 'b'
. So if send a string to args
, even in parentheses (still a sting), each character will be treated as a single parameter.
However, Python is so integrated and is not like JavaScript where extra arguments can be tolerated. Instead, it throws an TypeError
to complain.