Frequency of list in list in python -

i have found several questions regarding finding frequency of value in list. though haven't found regarding finding frequency of list in list. (or ndarray in ndarray)

in essence want find unique rows in :

ndarray: [[ 3.95428571 5.67428571]

 [ 3.795       4.67166667]  [ 5.05        6.79      ]  [ 4.54333333  6.16666667]  [ 4.7175      6.31      ]  [ 4.81        6.41      ]  [ 3.82166667  5.34666667]  [ 4.16        6.315     ]  [ 3.915       4.855     ]  [ 4.44        6.57      ]  [ 5.1         6.78      ]  [ 4.03        6.655     ]  [ 3.71        6.22      ]  [ 4.57142857  5.51      ]  [ 3.67        5.45      ]  [ 4.048       5.484     ]  [ 4.24714286  5.31142857]  [ 4.125       6.175     ]  [ 4.72        4.18      ]  [ 4.02125     5.82625   ]  [ 3.729       5.688     ]  [ 4.17666667  5.80666667]  [ 4.08        6.102     ]  [ 5.05        7.1       ]  [ 4.22        4.968     ]  [ 3.6625      5.9625    ]  [ 4.444       5.832     ]  [ 4.395       7.09      ]  [ 4.39        5.        ]  [ 4.745       5.995     ]  [ 4.81        7.25      ]  [ 3.74285714  6.22571429]  [ 5.52        4.38      ]  [ 3.92        4.1       ]  [ 3.525       5.91833333]  [ 3.85666667  6.09333333]  [ 3.42        5.87... 

and corresponding frequency. ( want plot 2d histogram)

any ideas/tips/solutions ?

you should have @ numpy.histogram2d