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README.md

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 Introduction
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 Website for more information [sscha.eu](http://sscha.eu/).
 
 The full documentation of the package is in the [python-sscha.pdf](https://github.com/SSCHAcode/python-sscha/blob/master/python-sscha.pdf) file, in the root directory of this repository
 
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+Subscriptions to the 2023 School are open!
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+Visit the official [webpage](http://sscha.eu/Schools/2023/home/) to learn more about the in presence school on the sscha code about how to compute thermodynamic properties of the matter, accounting for anharmonicity and quantum fluctuations of ions!
+The school will be held in San Sebastian, Spain, between 26-30 June.
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 What is python-sscha?
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