Read a file from the Internet to give to an arbitrary function

read_from_web.py

import re
import urllib
from io import BytesIO


# If the fname you gave me looks like a URL...
if re.match(r'https?://.+\..+/.+?', fname) is not None:
    try:
        data = urllib.request.urlopen(fname).read()
    except urllib.error.HTTPError as e:
        raise IOError('Could not retrieve url: ', e)
    fname = BytesIO(data)

# This next bit is made up code:
my_data = my_library.read_file(fname)