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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 group_bar(self, column_label, **vargs):
 """Plot a bar chart for the table. The values of the specified column are grouped and counted, and one bar is produced for each group. Note: This differs from ``bar`` in that there is no need to specify bar heights; the height of a category's bar is the number of copies of that category in the given column. This method behaves more like ``hist`` in that regard, while ``bar`` behaves more like ``plot`` or ``scatter`` (which require the height of each point to be specified). Args: ``column_label`` (str or int):
 The name or index of a column Kwargs: overlay (bool):
 create a chart with one color per data column; if False, each will be displayed separately. width (float):
 The width of the plot, in inches height (float):
 The height of the plot, in inches vargs: Additional arguments that get passed into `plt.bar`. See http://matplotlib.org/api/pyplot_api.html#matplotlib.pyplot.bar for additional arguments that can be passed into vargs. """

        self.group(column_label).bar(column_label, **vargs)