Quick Sort in Python

quick_sort.py

class Sorter:
    def __init__(self,data):
        self.orig = data.copy()
        self.data = data

    def do_qsort(self):
        print("Original data",self.orig)
        self.run_qsort(0,len(self.data)-1)
        print("Sorted data  ",self.data)

    def run_qsort(self,i,j):
        self.swap(i,int((i+j)/2))
        k=i+1
        for m in range(i+1,j+1):
            if self.data[m]<self.data[i]:
                self.swap(m,k)
                k+=1
        self.swap(i,k-1)
        if i+1<k:
            self.run_qsort(i,k-1)
        if k<j:
            self.run_qsort(k,j)

    def swap(self,i,j):
        self.data[i], self.data[j] = self.data[j], self.data[i]

Sorter([5,3,1,0,2,4,9,7,6,8]).do_qsort()
Sorter([9,8,7,6,5,4,3,2,1,0]).do_qsort()
Sorter([2,2,2,2,1,1,1,1,0,0]).do_qsort()

$ python quick_sort.py
Original data [5, 3, 1, 0, 2, 4, 9, 7, 6, 8]
Sorted data   [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
Original data [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
Sorted data   [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
Original data [2, 2, 2, 2, 1, 1, 1, 1, 0, 0]
Sorted data   [0, 0, 1, 1, 1, 1, 2, 2, 2, 2]