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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 _change_height(self, ax, new_value):
 """Make bars in horizontal bar chart thinner"""

        for patch in ax.patches:
            current_height = patch.get_height()
            diff = current_height - new_value

            # we change the bar height
            patch.set_height(new_value)

            # we recenter the bar
            patch.set_y(patch.get_y() + diff * .5)