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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 makedir(dir_name):
 """ "Strong" directory maker. "Strong" version of `os.mkdir`. If `dir_name` already exists, this deletes it first. **Parameters** **dir_name** : string Path to a file directory that may or may not already exist. **See Also:** :func:`tabular.io.delete`, `os <http://docs.python.org/library/os.html>`_ """

    if os.path.exists(dir_name):
        delete(dir_name)
    os.mkdir(dir_name)