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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 weekly_plots( df, variable, renormalize = True, plot = True, scatter = False, linestyle = "-", linewidth = 1, s = 1 ):
 """ Create weekly plots of a variable in a DataFrame, optionally renormalized. It is assumed that the variable `days_through_week` exists. """

    if not "days_through_week" in df.columns:
        log.error("field days_through_week not found in DataFrame")
        return False
    weeks = []
    for group in df.groupby(df.index.week):
        weeks.append(group[1])
    scaler = MinMaxScaler()
    plt.ylabel(variable);
    for week in weeks:
        if renormalize:
            values = scaler.fit_transform(week[[variable]])
        else:
            values = week[variable]
        if plot:
            plt.plot(week["days_through_week"], values, linestyle = linestyle, linewidth = linewidth)
        if scatter:
            plt.scatter(week["days_through_week"], values, s = s)
    plt.xticks(
        [     0.5,       1.5,         2.5,        3.5,      4.5,        5.5,      6.5],
        ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"]
    )