Binary search recursive

binary_search.py

def binarySearch (arr, l, r, x): 
    if r >= l:   
        mid = l + (r - l)/2
        if arr[mid] == x: 
            return mid 
        elif arr[mid] > x: 
            return binarySearch(arr, l, mid-1, x) 
        else: 
            return binarySearch(arr, mid+1, r, x) 
    else: 
        return -1