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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_p(dirname):
 """ Like "mkdir -p", make a dir recursively, but do nothing if the dir exists Args: dirname(str):
 """

    assert dirname is not None
    if dirname == '' or os.path.isdir(dirname):
        return
    try:
        os.makedirs(dirname)
    except OSError as e:
        if e.errno != errno.EEXIST:
            raise e