Fixed set_input_and_output in case exec_network is not set (#3011)

Author: Anna Grebneva

tools/accuracy_checker/openvino/tools/accuracy_checker/evaluators/custom_evaluators/base_models.py

@@ -195,13 +195,14 @@ def automatic_model_search(self, network_info):
         return model, weights
 
     def set_input_and_output(self):
-        has_info = hasattr(self.exec_network, 'input_info')
-        input_info = self.exec_network.input_info if has_info else self.exec_network.inputs
+        network = self.exec_network if self.exec_network is not None else self.network
+        has_info = hasattr(network, 'input_info')
+        input_info = network.input_info if has_info else network.inputs
         input_blob = next(iter(input_info))
         with_prefix = input_blob.startswith(self.default_model_suffix)
         if self.input_blob is None or with_prefix != self.with_prefix:
             if self.output_blob is None:
-                output_blob = next(iter(self.exec_network.outputs))
+                output_blob = next(iter(network.outputs))
             else:
                 output_blob = (
                     '_'.join([self.default_model_suffix, self.output_blob])