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+# PySASA  - A GUI to calculate the solvent accessible-surface area
+
+## require
+- python version 3
+- numpy
+
+# usage
+>python3 Py3SASA.py  
+
+in my computer, it needs 1-2 min to calculate the protein 1be9.pdb, you can find it in the ./test/pdb/ directory.