Reads in a json document and returns a native python
    datastructure.

def read_json_document(title):
    """
    Reads in a json document and returns a native python
    datastructure.
    """
    if not title.endswith('.json'):
        juicer.utils.Log.log_warn("File name (%s) does not end with '.json', appending it automatically." % title)
        title += '.json'

    if not os.path.exists(title):
        raise IOError("Could not find file: '%s'" % title)

    f = open(title, 'r')
    doc = f.read()
    f.close()

    return load_json_str(doc)