Symbolic response doesn't need to pre-import symmath any more, I think?

common/lib/capa/capa/responsetypes.py

@@ -1200,8 +1200,6 @@ class SymbolicResponse(CustomResponse):
 
     def setup_response(self):
         self.xml.set('cfn', 'symmath_check')
-        code = "from symmath import *"
-        exec code in self.context, self.context
         CustomResponse.setup_response(self)
 
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