(self, key)
Fast extraction of the i,j element from the matrix
            This function is for private use only because is unsafe:
                1. Does not check on the value of key it expects key to be a integer tuple (i,j)
                2. Does not check bounds
Fast extraction of the i,j element from the matrix
            This function is for private use only because is unsafe:
                1. Does not check on the value of key it expects key to be a integer tuple (i,j)
                2. Does not check bounds
Fast extraction of the i j element from the matrix This function is for private use only because is unsafe : 1 . Does not check on the value of key it expects key to be a integer tuple ( i j ) 2 . Does not check bounds
def __get_element(self, key):
        '''
        Fast extraction of the i,j element from the matrix
            This function is for private use only because is unsafe:
                1. Does not check on the value of key it expects key to be a integer tuple (i,j)
                2. Does not check bounds
        '''
        if key in self.__data:
            return self.__data[key]
        else:
            return self.ctx.zero
def __get_element ( self , key ) : if key in self . __data : return self . __data [ key ] else : return self . ctx . zero