diff --git a/source/machine-learning/pytorch.md b/source/machine-learning/pytorch.md
index 2c65971..98c4f67 100644
--- a/source/machine-learning/pytorch.md
+++ b/source/machine-learning/pytorch.md
@@ -6,3 +6,11 @@
   - convert tensor to standard Python number
   - only works for tensors with one element - otherwise an exception is raised
   - implicitly moves the value to the CPU
+
+## shape
+
+Example:
+
+```python
+batch_size, sequence_length = attention_mask.shape
+```