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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 write_input(self, output_dir, make_dir_if_not_present=True, include_cif=False):
 """ Writes a set of VASP input to a directory. Args: output_dir (str):
 Directory to output the VASP input files make_dir_if_not_present (bool):
 Set to True if you want the directory (and the whole path) to be created if it is not present. include_cif (bool):
 Whether to write a CIF file in the output directory for easier opening by VESTA. """

        vinput = self.get_vasp_input()
        vinput.write_input(
            output_dir, make_dir_if_not_present=make_dir_if_not_present)
        if include_cif:
            s = vinput["POSCAR"].structure
            fname = Path(output_dir) / ("%s.cif" % re.sub(r'\s', "", s.formula))
            s.to(filename=fname)