fix typo

docs/convert.rst

@@ -5,18 +5,18 @@ PegasusIO stores data as *MultimodalData* objects, and each *MultimodalData* has
 
 *AnnData* is the annotated data matrix object provided by anndata_ package.
 
-Let ``mmd`` be a PegasusIO *MultimodalData* object. Use the following code to convert its default *UnimodalData* to *AnnData*::
+Let ``mmdata`` be a PegasusIO *MultimodalData* object. Use the following code to convert its default *UnimodalData* to *AnnData*::
 
-    >>> adata = mdd.to_anndata()
+    >>> adata = mmdata.to_anndata()
 
 And ``adata`` is the wanted *AnnData* object.
 
 Now let ``adata`` be an *AnnData* object (See `anndata reading documentation`_ for how to load file to *AnnData*). Use the following code to convert it to PegasusIO *MultimodalData*::
 
     >>> import pegasusio as io
-    >>> mmd = io.MultimodalData(adata)
+    >>> mmdata = io.MultimodalData(adata)
 
-And ``mmd`` is the wanted *MultimodalData* object.
+And ``mmdata`` is the wanted *MultimodalData* object.
 
 .. _anndata: https://anndata.readthedocs.io/en/stable/anndata.AnnData.html
 .. _anndata reading documentation: https://anndata.readthedocs.io/en/stable/api.html#reading