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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def prepare_calc_dir(self):
        '''
        Prepare the calculation directory for VASP execution.
        This needs to be re-implemented for each local setup.
        The following code reflects just my particular setup.
        '''
        with open("vasprun.conf","w") as f:
            f.write('NODES="nodes=%s:ppn=%d"\n' % (self.nodes, self.ppn))
            f.write('BLOCK=%d\n' % (self.block,))
            if self.ncl :
                f.write('NCL=%d\n' % (1,))