import array as arr
a = arr.array('d', [1, 2, 3])
for x in a:
   print (x)

1.0
2.0
3.0

import array as arr
a = arr.array('d', [1, 2, 3])
l = len(a)
idx =0
while idx<l:
   print (a[idx])
   idx+=1

import array as arr
a = arr.array('d', [1, 2, 3])
l = len(a)
for x in range(l):
   print (a[x])