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re.complile failure in a SageWS (Vertical Bar character)

I was trying to use a Python Cookbook recipe (https://www.safaribooksonline.com/library/view/python-cookbook-2nd/0596007973/ch01s19.html) for multiple regular expression matches and substitutions in a Sagemath Cloud Sage Worksheet (final usage is for altering the __latex_/_repr_ attributes of an object). The code from the cookbook is below:

import re
def multiple_replace(txt, adict):
    rx = re.compile('|'.join(map(re.escape, adict)))
    def one_xlat(match):
        return adict[match.group(0)]
    return rx.sub(one_xlat, txt)


txt = "Larry Wall is the creator of Perl"
adict = {
  "Larry Wall" : "Guido van Rossum",
  "creator" : "Benevolent Dictator for Life",
  "Perl" : "Python",
}

print(multiple_replace(txt, adict))

When I run this code in the Worksheet I get the error:

Error in lines 13-13
Traceback (most recent call last):
  File "/projects/PROJECT/sagemathcloud/sage_server.py", line 873, in execute
    exec compile(block+'\n', '', 'single') in namespace, locals
  File "", line 1, in <module>
  File "", line 5, in multiple_replace
  File "", line 4, in one_xlat
IndexError: no such group

If I run the same code on a Sagemath Cloud IPython Notebook, Windows/Linux Python 2.7 session, or Windows/Linux Python 3.4 session the code outputs the correct result.

I started debugging and found that Sage doesn't like the '|' in the compiled string. If I change the character to another (e.g. ',') I no longer get the error ... though the code no longer functions with anything other than the '|'. I also tried to substitute '|' with unichr(int('007c', 16)) which results in the same error.

Has anyone seen anything like this before? I tried to search for it, but it seems so niche I didn't find any results. Any ideas for a workaround?

Thanks Matt