def _check_steps(a, b):
 if (a.step != 1):
  raise ValueError(('a.step must be equal to 1, got: %s' % a.step))
 if (b.step != 1):
  raise ValueError(('b.step must be equal to 1, got: %s' % b.step))

def _check_steps ( a , b ) : if ( a . step != 1 ) : raise ValueError ( ( 'a.step must be equal to 1, got: %s' % a . step ) ) if ( b . step != 1 ) : raise ValueError ( ( 'b.step must be equal to 1, got: %s' % b . step ) )
check that the steps of a and b are both 1 .