The regular expression pattern and string have to be of the same type. If you're matching a regular string, you need a string pattern. If you're matching a byte string, you need a bytes pattern.
In this case m.read() returns a byte string, so you need a bytes pattern. In Python 3, regular strings are unicode strings, and you need the b modifier to specify a byte string literal:
linkregex = re.compile(b'')
