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Python Python Basics (Retired) Putting the "Fun" Back in "Function" Functions

Trevor Devalle
PLUS
Trevor Devalle
Courses Plus Student 992 Points
Posted by Trevor Devalle
Trevor Devalle
Courses Plus Student 992 Points

Python - typeError: Can't convert 'int' object to str implicitly

I really can't understand what is wrong with my code. I also tried it on my computer and everything works!

I will appreciate any kind of help.

Thank you! This error is drive me crazy!

functions.py 
# add_list([1, 2, 3]) should return 6
# summarize([1, 2, 3]) should return "The sum of [1, 2, 3] is 6."
# Note: both functions will only take *one* argument each.

def add_list(intlist):
  return sum(intlist)

def summarize(intlist):
  strintlist = ''.join(str(e) for e in intlist)    
  return 'The sum ' + strintlist + ' is ' + sum(intlist) + "."

1 Answer

Charles Lee
Charles Lee
17,825 Points 
def summarize(intlist):
  strintlist = ''.join(str(e) for e in intlist)    
  return 'The sum ' + strintlist + ' is ' + sum(intlist) + "."

The problem here is that in the last line of this method, we're trying to concat a str and an integer together. Python, by default, will not automatically convert that for you. 

def summarize(intlist):
  strintlist = ''.join(str(e) for e in intlist)    
  return 'The sum ' + strintlist + ' is ' + str(sum(intlist)) + "."

A better way for string interpolation is to use the .fortmat method. 

def summarize(intlist):
  strintlist = ''.join(str(e) for e in intlist)    
  return 'The sum {} is {}.".format(strintlist, sum(intlist))

Hope this helps! :]