def is_lval(t):
 if (not t):
  return False
 i = iter(t)
 if (i.next() not in IDENTIFIER_START):
  return False
 return all(((e in IDENTIFIER_PART) for e in i))

def is_lval ( t ) : if ( not t ) : return False i = iter ( t ) if ( i . next ( ) not in IDENTIFIER_START ) : return False return all ( ( ( e in IDENTIFIER_PART ) for e in i ) )
does not chceck whether t is not resticted or internal .