Question: 
Write a function to calculate the sum of the negative numbers of a given list of numbers using lambda function.


Model's Code:
def sum_negativenum(nums):
    return sum(filter(lambda x: x < 0, nums))



Sample Correct Code:
def sum_negativenum(nums):
  sum_negativenum = list(filter(lambda nums:nums<0,nums))
  return sum(sum_negativenum)


Asserts:
assert sum_negativenum([2, 4, -6, -9, 11, -12, 14, -5, 17])==-32
assert sum_negativenum([10,15,-14,13,-18,12,-20])==-52
assert sum_negativenum([19, -65, 57, 39, 152,-639, 121, 44, 90, -190])==-894


Tests:
Test 1 of 3: PASS
Test 2 of 3: PASS
Test 3 of 3: PASS

Test 133 of 974: 100/133 (75.18796992481202%): success