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Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today. # 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?

Thank you!!!

instances.py
```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.