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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 add_text_table(self, rows, r0, dr, **kwargs):
 """ Add text to a plot in a grid fashion. `rows` is a list of lists (the rows). Each row contains the columns, each column is text to add to the plot. `r0` is a tuple `(x, y)` that positions the initial text. `dr` is a tuple `(dx, dy)` that determines the column and row spacing. Any keyword arguments will be passed to `matplotlib.pyplot.text`. Example: #!python horizontalalignment='left', verticalalignment='top') [1]: http://matplotlib.org/api/pyplot_api.html#matplotlib.pyplot.text """

        for m, row in enumerate(rows):
            for n, column in enumerate(row):
                self.plt.text(r0[0] + dr[0] * n, r0[1] + dr[1] * m, column,
                    transform=self.plt.axes.transAxes, **kwargs)