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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 plot_memory(calc_id=-1):
 """ Plot the memory occupation """

    dstore = util.read(calc_id)
    plots = []
    for task_name in dstore['task_info']:
        mem = dstore['task_info/' + task_name]['mem_gb']
        plots.append((task_name, mem))
    plt = make_figure(plots)
    plt.show()