#!/usr/bin/env python3
import io
class copen(io.IOBase):
    def __init__(self,name=None,mode='rt'):
        """Open a file to test an issue of an iterator expecting bytes when it gets, and should expect, str."""
        if mode != 'rt':
            exit(f"in topen.py/copen.__init__: this test needs mode 'rt', not {mode!r} ... aborting.")
        self.f = open(name,mode)
        return
    def close(self):
        result = self.f.close()
        return result
    def __getattr__(self,*args):
        return getattr(self.f,*args)
f = copen('topen.py','rt')
l = [x for x in f] # the exception happens here
f.close()
for x in l:
    print(x)
exit('DONE')