Changed 'Returns' to 'Return' in the doc

src/sage/combinat/root_system/reflection_group_real.py

@@ -709,7 +709,7 @@ def simple_root_index(self, i):
 
     def bruhat_cone(self, x, y, side = 'upper'):
         r"""
-        Returns the polyhedral cone generated by the set of positive roots ``beta`` where ``s_beta`` is the reflection corresponding to ``beta`` and:
+        Return the polyhedral cone generated by the set of positive roots ``beta`` where ``s_beta`` is the reflection corresponding to ``beta`` and:
 
         For ``side`` = ``'upper'``: ``s_beta`` ``x`` covers ``x`` and ``x`` <= ``s_beta`` ``x`` <= ``y``.