[Python] Inherit from scikit-learn's LassoCV model

I tried to extend scikit-learn's RidgeCV model using inheritance:

from sklearn.linear_model import RidgeCV, LassoCV

class Extended(RidgeCV):
def __init__(self, *args, **kwargs):
super(Extended, self).__init__(*args, **kwargs)

def example(self):
print 'Foo'


x = [[1,0],[2,0],[3,0],[4,0], [30, 1]]
y = [2,4,6,8, 60]
model = Extended(alphas = [float(a)/1000.0 for a in range(1, 10000)])
model.fit(x,y)
print model.predict([[5,1]])


It worked perfectly fine, but when I tried to inherit from LassoCV, it yielded the following traceback:

Traceback (most recent call last):
File "C:/Python27/so.py", line 14, in <module>
model.fit(x,y)
File "C:\Python27\lib\site-packages\sklearn\linear_model\coordinate_descent.py", line 1098, in fit
path_params = self.get_params()
File "C:\Python27\lib\site-packages\sklearn\base.py", line 214, in get_params
for key in self._get_param_names():
File "C:\Python27\lib\site-packages\sklearn\base.py", line 195, in _get_param_names
% (cls, init_signature))
RuntimeError: scikit-learn estimators should always specify their parameters in the signature of their __init__ (no varargs). <class '__main__.Extended'> with constructor (<self>, *args, **kwargs) doesn't follow this convention.


Can somebody explain how to fix this?

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