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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 offline_plotly_scatter3d(df, x=0, y=1, z=-1):
 """ Plot an offline scatter plot colored according to the categories in the 'name' column. >> df = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/iris.csv') >> offline_plotly(df) """

    data = []
    # clusters = []
    colors = ['rgb(228,26,28)', 'rgb(55,126,184)', 'rgb(77,175,74)']

    # df.columns = clean_columns(df.columns)

    x = get_array(df, x, default=0)
    y = get_array(df, y, default=1)
    z = get_array(df, z, default=-1)
    for i in range(len(df['name'].unique())):
        name = df['Name'].unique()[i]
        color = colors[i]
        x = x[pd.np.array(df['name'] == name)]
        y = y[pd.np.array(df['name'] == name)]
        z = z[pd.np.array(df['name'] == name)]

        trace = dict(
            name=name,
            x=x, y=y, z=z,
            type="scatter3d",
            mode='markers',
            marker=dict(size=3, color=color, line=dict(width=0)))
        data.append(trace)

    layout = dict(
        width=800,
        height=550,
        autosize=False,
        title='Iris dataset',
        scene=dict(
            xaxis=dict(
                gridcolor='rgb(255, 255, 255)',
                zerolinecolor='rgb(255, 255, 255)',
                showbackground=True,
                backgroundcolor='rgb(230, 230,230)'
            ),
            yaxis=dict(
                gridcolor='rgb(255, 255, 255)',
                zerolinecolor='rgb(255, 255, 255)',
                showbackground=True,
                backgroundcolor='rgb(230, 230,230)'
            ),
            zaxis=dict(
                gridcolor='rgb(255, 255, 255)',
                zerolinecolor='rgb(255, 255, 255)',
                showbackground=True,
                backgroundcolor='rgb(230, 230,230)'
            ),
            aspectratio=dict(x=1, y=1, z=0.7),
            aspectmode='manual'
        ),
    )

    fig = dict(data=data, layout=layout)

    # IPython notebook
    # plotly.iplot(fig, filename='pandas-3d-iris', validate=False)

    url = plotly.offline.plot(fig, filename='pandas-3d-iris', validate=False)
    return url