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CONTRIBUTING.md

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+#Contributing to PM code
+
+In order to make a contribution to this pakcage, tehre are just a few things to have in mind.
+
+__NOTE__: _Please make sure that there is already no exisiting [issue]((https://github.com/guillermo-carrasco/pm/issues)) related with whatever you want to report._
+
+####To contribute:
+1. Create an issue describing the bug/suggestion/improvement/... [here](https://github.com/guillermo-carrasco/pm/issues).
+2. Fork this repository to your GitHub account
+3. Make the necessary changes/additions to your forked pm repository
+4. Please *make sure* that you've documented your code and changes using [sphinx](http://sphinx.readthedocs.org/en/latest/tutorial.html) syntax, as the documentation will be automatically generated using this engine, and published to ReadTheDocs \<add link to read the docs>
+5. Pull Request and wait for some responsible to review and merge the code
+
+That's it! And thanks a lot!