remove comment in python

#a
#b
import sys  #c
from tokenize import tokenize, untokenize, COMMENT, NEWLINE, NL
from io import BytesIO
ret = []  #d
with open(sys.argv[1]) as f:
    for line in f:
        in_comment = False  #e
        for tok in tokenize(BytesIO(line.encode('utf-8')).readline):
            if tok.type == COMMENT:
                in_comment = True
                continue
            elif in_comment and tok.type == NL:
                in_comment = False
                continue
            elif in_comment and tok.type == NEWLINE:
                in_comment = False
                ret.append((tok.type, tok.string))
                continue
            else:  #f
                ret.append((tok.type, tok.string))
print(untokenize(ret).decode('utf-8'))