Cpp code to python help!! (Difficulties in understanding for loop in python)

Question

for (k = size / 2;k > 0;k /= 2)
{
for (j = k;j < size;j++)
{
for (i = j - k;i >= 0;i -= k)
{
if (array[i + k] >= array[i])
{
break;
}
else
{
mid = array[i];
array[i] = array[i + k];
array[i + k] = mid;
}
}
}
}
return 0;
}