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Start your free trialSon-Hai Nguyen
2,481 PointsI need help on this ```combiner()``` exercise
Please have a look at my following method. I tested it on Worksplaces, it worked just fine just like the requirement, but somehow the Recheck work kept saying there's a TypeError: sequence item 0: expected str instance, list found
Is there anyone know what I missed?
Thank you!!!
def combiner(*args):
numLs = []
strLs = []
for a in args:
if isinstance(a, (int, float)):
numLs.append(a)
else:
strLs.append(a)
sumInt = str(sum(numLs))
strLs.append(sumInt)
return ''.join(strLs)
combiner("apple", 5.2, "dog", 8)
3 Answers
KRIS NIKOLAISEN
54,972 Points*args accepts a variable list of arguments (so there can be more than one). The challenge will pass in a single list (any number of items but they will be enclosed in brackets so there will only be one list)
The easiest fix to your code is just remove the * from your parameter
KRIS NIKOLAISEN
54,972 PointsThe function takes a single argument. If you want to test in a workspace try:
print(combiner(["apple", 5.2, "dog", 8]))
Son-Hai Nguyen
2,481 PointsThanks Kris, for your answer. But what does it mean? Doesnt the *args
stand for a list of arguments? How to iterate through it (since it's still a list right? I saw the [] here) if it's a single argument?
KRIS NIKOLAISEN
54,972 PointsIf you add print statements you better see what is going on:
def combiner(*args):
numLs = []
strLs = []
for a in args:
print(a)
if isinstance(a, (int, float)):
numLs.append(a)
else:
strLs.append(a)
sumInt = str(sum(numLs))
strLs.append(sumInt)
print(strLs)
return ''.join(strLs)
print(combiner(["apple", 5.2, "dog", 8]))
In the loop a is a list so since it since it isn't an int or float it is appended to strLs. Since that is the only argument there are no numbers to sum so sumInt = '0'. Append this to strLs you end up with [['apple', 5.2, 'dog', 8], '0']. At which point using join on a list and a string causes the error.
Son-Hai Nguyen
2,481 PointsSon-Hai Nguyen
2,481 PointsGreat!!! It sounds weird to pass all variables in as a single list anw