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Son-Hai Nguyen2,481 Points
I 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?
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)
*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
The function takes a single argument. If you want to test in a workspace try:
print(combiner(["apple", 5.2, "dog", 8]))
If 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.