array.append(v)

import array as arr
a = arr.array('i', [1, 2, 3])
a.append(10)
print (a)

array('i', [1, 2, 3, 10])

array.insert(i, v)

import array as arr
a = arr.array('i', [1, 2, 3])
a.insert(1,20)
print (a)

array('i', [1, 20, 2, 3])

array.extend(x)

import array as arr
a = arr.array('i', [1, 2, 3, 4, 5])
b = arr.array('i', [6,7,8,9,10])
a.extend(b)
print (a)

array('i', [1, 2, 3, 4, 5, 6, 7, 8, 9, 10])