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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 mkdir(self, target_folder):
 """ Create a folder on S3. Examples -------- Making directory: path/to/my_folder """

        self.printv("Making directory: %s" % target_folder)
        self.k.key = re.sub(r"^/|/$", "", target_folder) + "/"
        self.k.set_contents_from_string('')
        self.k.close()