BatchError is unprintable using default constructor (one string)

[ShadowLNC]

This one should be pretty simple, I hope.

Here's the constructor signature: def __init__(self, reason, resp=None, content=None):, which doesn't require resp to be defined, and I can see it is not defined most of the time, for example, in googleapiclient/http.py.

Then, given the representation method:

def __repr__(self):
      return '<BatchError %s "%s">' % (self.resp.status, self.reason)

Which is also the string method:

__str__ = __repr__

This results in unprintable exceptions where resp is undefined, which is not very helpful when attempting to understand the error (e.g. #164).

[KillianKemps]

👍 I encountered this same issue. Fortunately, I could fix my problem because you documented another issue #164 very well

[theacodes]

Thanks for reporting this. If anyone wants to send a PR to fix this, I'll be happy to review and merge.