DOC remove extra colon from doc string
@@ -1819,7 +1819,7 @@ def pairwise_kernels(X, Y=None, metric="linear", filter_params=False,
If Y is given (default is None), then the returned matrix is the pairwise
kernel between the arrays from both X and Y.
- Valid values for metric are::
+ Valid values for metric are:
['additive_chi2', 'chi2', 'linear', 'poly', 'polynomial', 'rbf',
'laplacian', 'sigmoid', 'cosine']
