def multiple_replace(dictionary, text):
    """Multiple replace

    Python Cookbook 3.14 page 88 and page 90
    """

    import re
    
    #Create a regular expression from all of the dictionary keys
    #matching only entire words
    #regex = re.compile("|".join(map(re.escape, dictionary.keys())))
    regex = re.compile(r'\b'+ \
                       r'\b|\b'.join(map(re.escape, dictionary.keys()))+ \
                       r'\b' )

    #For each match, lookup the corresponding value in the dictionary
    return regex.sub(lambda match: dictionary[match.group(0)], text)


def merge_dictionaries(D1,D2):
    """merge_dictionaries(D1,D2)
  
       Merge two disjoint dictionaries
       The first argument D1 is modified to hold the result of the merger.
       If dictionaries are not disjoint an exception is raised
    """
    import types

    for k in D2.keys():
        val = D2[k]
        if not D1.has_key(k):
            D1[k] = val        
        else:
            print 'Dictionaries not disjoint'
            raise Exception
  
    return D1