code: def get_global_variable(self, name):
          
          p = ffi.lib.LLVMPY_GetNamedGlobalVariable(self, _encode_string(name))
          if not p:
              raise NameError(name)
          return ValueRef(p, 'global', dict(module=self))
docs: Get a ValueRef pointing to the global variable named *name*.
          NameError is raised if the symbol isn't found.