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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 set_progress(how):
 """ Enables or disables the progress bars for the loading, writing and downloading of datasets :param how: True if you want the progress bar, False otherwise :return: None Example:: import gmql as gl gl.set_progress(True) # abilitates progress bars gl.set_progress(False) # removes progress bars """

    global __progress_bar
    if isinstance(how, bool):
        __progress_bar = how
    else:
        raise ValueError(
            "how must be a boolean. {} was found".format(type(how)))