Find the length between 2 co-ordinates.  The co-ordinates are made of integers between -20 and 20 and will be given in the form of a 2D array:

(0,0) and (5,-7) would be [ [ 0 , 0 ] , [ 5, -7 ] ]

The function must return the answer rounded to 2 decimal places in the form of a string.

```python
length_of_line([[0, 0], [5, -7]]) => "8.60"
```

If the 2 given co-ordinates are the same, the returned length should be "0.00"

Source: codewars | Difficulty: EASY

Starter code: def length_of_line(array):
	

Solutions:
from math import sqrt

def length_of_line(array):
	(x1, y1, x2, y2) = (array[0][0], array[0][1], array[1][0], array[1][1])
	return '{:.2f}'.format(sqrt((x2 - x1) ** 2 + (y2 - y1) ** 2))


import math

def length_of_line(array):
	return '{:.02f}'.format(math.sqrt((array[1][0] - array[0][0]) ** 2 + (array[1][1] - array[0][1]) ** 2))


from math import hypot

def length_of_line(array):
	((a, b), (c, d)) = array
	return f'{hypot(a - c, b - d):.2f}'


def length_of_line(pts):
	return f'{sum(((a - b) ** 2 for (a, b) in zip(*pts))) ** 0.5:.2f}'


def length_of_line(array):
	return '{:0.2f}'.format(((array[0][0] - array[1][0]) ** 2 + (array[0][1] - array[1][1]) ** 2) ** 0.5)


from itertools import starmap
from operator import sub
from math import hypot

def length_of_line(array):
	return '{:.2f}'.format(hypot(*starmap(sub, zip(*array))))


import math

def length_of_line(array):
	return '%.2f' % math.hypot(array[1][0] - array[0][0], array[1][1] - array[0][1])