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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 upload_index_file(self, test_address, timestamp):
 """ Create an index.html file with links to all the log files that were just uploaded. """

        global already_uploaded_files
        already_uploaded_files = list(set(already_uploaded_files))
        already_uploaded_files.sort()
        file_name = "%s/%s/index.html" % (test_address, timestamp)
        index = self.get_key(file_name)
        index_str = []
        for completed_file in already_uploaded_files:
            index_str.append("<a href='" + self.bucket_url + ""
                             "%s'>%s</a>" % (completed_file, completed_file))
        index.set_contents_from_string(
            "<br>".join(index_str),
            headers={"Content-Type": "text/html"})
        index.make_public()
        return "%s%s" % (self.bucket_url, file_name)