Make a function **"add"** that will be able to sum elements of **list** continuously and return a new list of sums.

For example: 

```
add [1,2,3,4,5] == [1, 3, 6, 10, 15], because it's calculated like 
this : [1, 1 + 2, 1 + 2 + 3, 1 + 2 + 3 + 4, 1 + 2 + 3 + 4 + 5]
```

If you want to learn more see https://en.wikipedia.org/wiki/Prefix_sum

Difficulty: introductory

Starter code:

def add(l):
	

Solutions:
from itertools import accumulate
def add(l):
    return list(accumulate(l)) if isinstance(l, list) and all(isinstance(x, int) for x in l) \
        else 'Invalid input'

from itertools import accumulate

def add(lst):
    return list(accumulate(lst))

from itertools import accumulate

def add(a):
    return isinstance(a, list) and all(isinstance(x, int) for x in a) and [*accumulate(a)] or "Invalid input"

def add(l):
    return [sum(l[:i+1]) for i in range(0,len(l))] if all(isinstance(x, int) for x in l) and isinstance(l, list) else 'Invalid input'

def add(l):
    return [sum(l[:i+1]) for i in range(len(l))]

add = lambda L: [sum(L[:i]) for i in range(1, len(L)+1)]

def add(lst):
    if not isinstance(lst, list):
        return "Invalid input"
    total, result = 0, []
    for n in lst:
        if not isinstance(n, int):
            return "Invalid input"
        total += n
        result.append(total)
    return result

from itertools import accumulate
def add(l):
    return list(accumulate(l))

add=lambda l:"Invalid input"if any(type(e)!=int for e in l)or type(l)!=list else[sum(l[:i+1])for i in range(len(l))]

def add(l):
    try:
        t = [l[0]]
        for i,j in enumerate(l[1:]):
            t.append(t[i]+ j)
        if sum(l)%1!=0 or sum(t)%1!=0 or type(l)!=list:
            return 'Invalid input'
        return t 
    except:
        return 'Invalid input'