Update README.md

README.md

@@ -1,12 +1,12 @@
 # NanoNet
 
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+[![Codacy Badge](https://api.codacy.com/project/badge/Grade/5186e15b951d4df6b4f20c2365870b7c)](https://app.codacy.com/app/freude/NanoNet?utm_source=github.com&utm_medium=referral&utm_content=freude/NanoNet&utm_campaign=Badge_Grade_Dashboard)
 
 <img src="https://user-images.githubusercontent.com/4588093/65398380-1f684380-ddfa-11e9-9e87-5aab6cf417b8.png" width="200">
 
@@ -30,10 +30,15 @@ git clone https://github.com/freude/NanoNet.git
 cd NanoNet
 ```
 
-`Nanonet` requires `openmpi` to be installed in the system.
+`Nanonet` requires `openmpi` to be installed in the system:
+Ubuntu
  ```bash
  sudo apt-get install libopenmpi-dev
  ```
+ MacOS
+ ```bash
+ brew install open-mpi
+ ```
  All other dependencies can be installed at once by invoking the following command
  from within the source directory: