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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 create_dir(path):
 """Creates a directory if it does not exist already. Args: path: The path of the directory to create. """

    full_path = abs_path(path)
    if not os.path.exists(full_path):
        try:
            os.makedirs(full_path)
        except OSError as e:
            # ignore the error for dir already exist.
            if e.errno != os.errno.EEXIST:
                raise