读取csv文件时出现python错误

Question

with open('repo-attributes.csv', 'rb') as repofile:
    reader = csv.DictReader(repofile)
    for repo in reader:
        g.add_vertex(name=repo['repository_url'],
            label=repo['repository_url'][19:],
            language='(unknown)' if repo['repository_language'] == 'null'
                else repo['repository_language'],
            watchers=int(repo['repository_watchers']))

This is my code. I am getting the error like as follows. I am new to python. kindly explain this.

Traceback (most recent call last):
  File "C:\Python34\github-network-analysis-master\process.py", line 9, in <module>
    for repo in reader:
  File "C:\Python34\lib\csv.py", line 109, in __next__
    self.fieldnames
  File "C:\Python34\lib\csv.py", line 96, in fieldnames
    self._fieldnames = next(self.reader)
_csv.Error: iterator should return strings, not bytes (did you open the file in text mode?)

Answer 1

Remove b , you are opening in binary mode hence the bytes error:

 with open('repo-attributes.csv', newline="") as repofile:

You can actually remove both as the default mode is r .

Answer 2

You are opening file in rb means read binary please open it in read mode. change your code to

...
...
with open('repo-attributes.csv', 'r')...
...
...

This will open file in read mode (not binary).

Answer 3

The last line of the trace tells where the error first occurred. Since you opened the file in binary mode, python is reading bytes. Your file is csv and opening it in read mode will suffice.

So instead of rb use r