add usage code

README.md

@@ -15,14 +15,25 @@ should probably proofread and complete it, then remove this comment. -->
 ## Model description
 
 This diffusion model is trained with the [🤗 Diffusers](https://github.com/huggingface/diffusers) library 
-on the `huggan/smithsonian_butterflies_subset` dataset.
+on the `huggan/smithsonian_butterflies_subset` dataset. Using this [script](https://github.com/huggingface/diffusers/blob/cde0ed162a127b17f1b4d4b16ff7f736cf04e690/examples/train_unconditional.py)
 
 ## Intended uses & limitations
 
 #### How to use
 
 ```python
-# TODO: add an example code snippet for running this diffusion pipeline
+from diffusers import DDPMPipeline
+
+model_id = "ceyda/ddpm-ema-butterflies-64"
+
+# load model and scheduler
+ddpm = DDPMPipeline.from_pretrained(model_id)  # you can replace DDPMPipeline with DDIMPipeline or PNDMPipeline for faster inference
+
+# run pipeline in inference (sample random noise and denoise)
+image = ddpm()["sample"]
+
+# save image
+image[0].save("ddpm_generated_image.png")
 ```
 
 #### Limitations and bias