diff --git a/nemo/collections/tts/g2p/models/t5.py b/nemo/collections/tts/g2p/models/t5.py
index 25f63d8d858a..19f976081687 100644
--- a/nemo/collections/tts/g2p/models/t5.py
+++ b/nemo/collections/tts/g2p/models/t5.py
@@ -46,17 +46,23 @@ class T5G2PModel(G2PModel, Exportable):
 
     @property
     def input_types(self) -> Optional[Dict[str, NeuralType]]:
-        return {
-            "input_ids": NeuralType(('B', 'T'), TokenIndex()),
-            "attention_mask": NeuralType(('B', 'T'), MaskType(), optional=True),
-            "labels": NeuralType(('B', 'T'), LabelsType()),
-        }
+        if self._input_types is None:
+            return {
+                "input_ids": NeuralType(('B', 'T'), TokenIndex()),
+                "attention_mask": NeuralType(('B', 'T'), MaskType(), optional=True),
+                "labels": NeuralType(('B', 'T'), LabelsType()),
+            }
+        return self._input_types
 
     @property
     def output_types(self) -> Optional[Dict[str, NeuralType]]:
-        return {"loss": NeuralType((), LossType())}
+        if self._output_types is None:
+            return {"loss": NeuralType((), LossType())}
+        return self._output_types
 
     def __init__(self, cfg: DictConfig, trainer: Trainer = None):
+        self._input_types = None
+        self._output_types = None
         self.world_size = 1
         if trainer is not None:
             self.world_size = trainer.num_nodes * trainer.num_devices
@@ -91,7 +97,11 @@ def forward(self, input_ids, attention_mask, labels):
     # ===== Training Functions ===== #
     def training_step(self, batch, batch_idx):
         input_ids, attention_mask, labels = batch
-        train_loss = self.forward(input_ids=input_ids, attention_mask=attention_mask, labels=labels,)
+        train_loss = self.forward(
+            input_ids=input_ids,
+            attention_mask=attention_mask,
+            labels=labels,
+        )
 
         self.log('train_loss', train_loss)
         return train_loss
@@ -126,7 +136,10 @@ def _setup_infer_dataloader(self, cfg) -> 'torch.utils.data.DataLoader':
 
     # Functions for inference
     @torch.no_grad()
-    def _infer(self, config: DictConfig,) -> List[int]:
+    def _infer(
+        self,
+        config: DictConfig,
+    ) -> List[int]:
         """
         Runs model inference.
 
@@ -161,7 +174,11 @@ def validation_step(self, batch, batch_idx, dataloader_idx=0, split="val"):
         input_ids, attention_mask, labels = batch
 
         # Get loss from forward step
-        val_loss = self.forward(input_ids=input_ids, attention_mask=attention_mask, labels=labels,)
+        val_loss = self.forward(
+            input_ids=input_ids,
+            attention_mask=attention_mask,
+            labels=labels,
+        )
 
         # Get preds from generate function and calculate PER
         labels_str = self._tokenizer.batch_decode(
@@ -287,15 +304,8 @@ def _prepare_for_export(self, **kwargs):
         }
 
     def _export_teardown(self):
-        self._input_types = self._output_types = None
-
-    @property
-    def input_types(self):
-        return self._input_types
-
-    @property
-    def output_types(self):
-        return self._output_types
+        self._input_types = None
+        self._output_types = None
 
     def input_example(self, max_batch=1, max_dim=44):
         """
@@ -307,7 +317,11 @@ def input_example(self, max_batch=1, max_dim=44):
         sentence = "Kupil sem si bicikel in mu zamenjal stol."
         input_ids = [sentence]
         input_encoding = self._tokenizer(
-            input_ids, padding='longest', max_length=self.max_source_len, truncation=True, return_tensors='pt',
+            input_ids,
+            padding='longest',
+            max_length=self.max_source_len,
+            truncation=True,
+            return_tensors='pt',
         )
         return (input_encoding.input_ids,)