I'm looking at this repl, I hope it is the right one (try and include it in future posts).

Problems

One thing is that you have imported the csv library multiple times which can cause problems.

You also used the word sum as your variable, which is one of Pythons defined words.

You should also specify in your open call that it should be read-only as to not break the file.

open(filePath, "r")

Also, with files (unless opened using with), you need to close them.

file.close()

Code

I rewrote what your code to be easier to read. Please note that this is what I thought it should do, maybe not what you intended. This is also only one of the functions you added.

The code is here:

import csv

def csv_sum(filePath):
  with open(filePath, newline='') as f: # Open file as f
    reader = csv.reader(f) # Create csv reader for f

    result = 0

    for line in reader: # lines in reader list
      for num in line: # nums in lines
        result += float(num) # Add num to result

  print(result) # Print result

csv_sum("test.csv") # Run csv_sum with file in same directory, should equal 10.5
csv_sum("files/test2.csv") # Run csv_sum with file in different directory, should equal 130.0

Would you be able to post the link of the repl it is not working with?