def merge(left, right):

  result = []

  i = j = 0

​

  while i < len(left) and j < len(right):

    if left[i] < right[j]:

      result.append(left[i])

      i += 1

    else:

      result.append(right[j])

      j += 1

​

  result.extend(left[i:])

  result.extend(right[j:])

​

  return result

​

def mergeSort(arr):

  step = 1 # Starting with sub-arrays of length 1

  length = len(arr)

​

  while step < length:

    for i in range(0, length, 2 * step):

      left = arr[i:i + step]

      right = arr[i + step:i + 2 * step]

​

    merged = merge(left, right)

​

    # Place the merged array back into the original array

    for j, val in enumerate(merged):

      arr[i + j] = val

​

    step *= 2 # Double the sub-array length for the next iteration

​

  return arr

​

mylist = [3, 7, 6, -10, 15, 23.5, 55, -13]

mysortedlist = mergeSort(mylist)

print(mysortedlist)

​