>>> from dic_filtres import filtrar_bidimensional

---- inici

>>> d = {
...   'a': {'x': 0, 'y': 10, 'z': 20},
...   'b': {'x': 1, 'y': 11, 'z': 21},
...   'c': {'x': 2, 'y': 12, 'z': 22},
...   'd': {'x': 3, 'y': 13, 'z': 23},
... }
>>> f = ['c', 'a']
>>> c = ['z']
>>> r = filtrar_bidimensional(d, f, c)
>>> r == {
...   'a': {'z': 20},
...   'c': {'z': 22},
... }
True

>>> f = []
>>> c = ['x', 'z']
>>> r = filtrar_bidimensional(d, f, c)
>>> r
{}

>>> f = ['b', 'd']
>>> c = []
>>> r = filtrar_bidimensional(d, f, c)
>>> r == {
...   'b': {},
...   'd': {},
... }
True

---- fi

>>> f = list(d.keys())
>>> c = list(d['a'].keys())
>>> r = filtrar_bidimensional(d, f, c)
>>> if r != d: print(r)

>>> f = ['b', 'c', 'd']
>>> c = ['x', 'y', 'z']
>>> r = filtrar_bidimensional(d, f, c)
>>> if r != {
...   'b': {'x': 1, 'y': 11, 'z': 21},
...   'c': {'x': 2, 'y': 12, 'z': 22},
...   'd': {'x': 3, 'y': 13, 'z': 23},
... }: print(r)

>>> f = ['b', 'd', 'a']
>>> c = ['x', 'y']
>>> r = filtrar_bidimensional(d, f, c)
>>> if r != {
...   'a': {'x': 0, 'y': 10},
...   'b': {'x': 1, 'y': 11},
...   'd': {'x': 3, 'y': 13},
... }: print(r)

>>> f = ['b']
>>> c = ['y', 'z']
>>> r = filtrar_bidimensional(d, f, c)
>>> if r != {
...   'b': {'y': 11, 'z': 21},
... }: print(r)