fix typo in RandomizedSearchCV docs
diff --git a/sklearn/model_selection/_search.py b/sklearn/model_selection/_search.py
index 0d0c15c54c468..b2345398aa92e 100644
--- a/sklearn/model_selection/_search.py
+++ b/sklearn/model_selection/_search.py
@@ -1075,7 +1075,7 @@ class RandomizedSearchCV(BaseSearchCV):
         will be represented by a ``cv_results_`` dict of::
 
             {
-            'param_kernel' : masked_array(data = ['rbf', rbf', 'rbf'],
+            'param_kernel' : masked_array(data = ['rbf', 'rbf', 'rbf'],
                                           mask = False),
             'param_gamma'  : masked_array(data = [0.1 0.2 0.3], mask = False),
             'split0_test_score'  : [0.8, 0.9, 0.7],

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#### Reference Issue

none
#### What does this implement/fix? Explain your changes.

Fixes a typo (missing ') in docs
#### Any other comments?

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add missing ' in RandomizedSearchCV docs
