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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 ensure_dir(d):
 """ Check to make sure the supplied directory path does not exist, if so, create it. The method catches OSError exceptions and returns a descriptive message instead of re-raising the error. :type d: str :param d: It is the full path to a directory. :return: Does not return anything, but creates a directory path if it doesn't exist already. """

    if not os.path.exists(d):
        try:
            os.makedirs(d)
        except OSError as oe:
            # should not happen with os.makedirs
            # ENOENT: No such file or directory
            if os.errno == errno.ENOENT:
                msg = twdd("""One or more directories in the path ({}) do not exist. If
                           you are specifying a new directory for output, please ensure
                           all other directories in the path currently exist.""")
                return msg.format(d)
            else:
                msg = twdd("""An error occurred trying to create the output directory
                           ({}) with message: {}""")
                return msg.format(d, oe.strerror)