Whitespace is significant

if 1+2==3:
  print 'Hello'
  if True:
       x=4.2
       print x+1.2
  else:
   msg='Not true'
   print msg

Python forces you to use the indentation that you would use anyway.

Python does not allow to obfuscate the structure of a program by using bogus indentations.

Have you ever seen code like this in C or C++?

/*  Warning: obfuscated C code! */
if( i == j )
    if( k == 0 )
        B[i][i] = 1.0 / A[i][i];
else
    B[i][j] = 4*k;