python - Append a tuple to a list - what's the difference between two ways? -


i wrote first "hello world" 4 months ago. since then, have been following coursera python course provided rice university. worked on mini-project involving tuples , lists. there strange adding tuple list me:

a_list = [] a_list.append((1, 2))       # succeed! tuple (1, 2) appended a_list a_list.append(tuple(3, 4))  # error message: valueerror: expecting array or iterable

it's quite confusing me. why specifying tuple appended using "tuple(...)" instead of simple "(...)" cause valueerror?

btw: used codeskulptor coding tool used in course

the tuple function takes 1 argument has iterable

tuple([iterable])

return tuple items same , in same order iterable‘s items.

try making 3,4 iterable either using [3,4] (a list) or (3,4) (a tuple)

for example

a_list.append(tuple((3, 4)))

will work


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