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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def message_index(index_url):
 """get message index of components for urllib2. Args: url(string):
 Returns: list: messages """

    idx = csv.reader(urllib2.urlopen(index_url), delimiter=':')
    messages = []
    for line in idx:
        messages.append(line)
    return messages