py3: zip returns iterator

[mathause]

In python 3 zip([1, 2], [3, 4]) does not return a list.

In [11]: mask = regionmask.defined_regions.giorgi.mask(airtemps)
    ...: print('All NaN? ',np.all(np.isnan(mask)))
    ...: 
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-11-2147f815f4cd> in <module>()
----> 1 mask = regionmask.defined_regions.giorgi.mask(airtemps)
      2 print('All NaN? ',np.all(np.isnan(mask)))

/home/mah/code/regionmask/regionmask/core/mask.py in _mask(self, lon_or_obj, lat, lon_name, lat_name, xarray, wrap_lon)
    132         raise NotImplementedError("Only method 'contains' is implemented")
    133 
--> 134     mask = func(lon, lat, data, numbers=self.numbers)
    135 
    136     if np.all(np.isnan(mask)):

/home/mah/code/regionmask/regionmask/core/mask.py in create_mask_contains(lon, lat, coords, fill, numbers)
    260         for c in cs:
    261             bbPath = mplPath.Path(c)
--> 262             sel = bbPath.contains_points(lonlat)
    263             out[sel] = numbers[i]
    264 

/home/mah/anaconda2/envs/regionmask3/lib/python3.5/site-packages/matplotlib/path.py in contains_points(self, points, transform, radius)
    510         if transform is not None:
    511             transform = transform.frozen()
--> 512         result = _path.points_in_path(points, radius, self, transform)
    513         return result
    514 

TypeError: float() argument must be a string or a number, not 'zip'