Not in general, only the indentation level of your statements is significant.
Also, the exact amount of indentation doesn't matter at all, but only the relative indentation of nested blocks.
if 1+2==3:
print 'Hello'
if True:
x=4.2
print x+1.2
else:
msg='Not true'
print msg
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;