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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 from_prev_calc(cls, prev_calc_dir, standardize=False, sym_prec=0.1, international_monoclinic=True, reciprocal_density=100, small_gap_multiply=None, **kwargs):
 """ Generate a set of Vasp input files for static calculations from a directory of previous Vasp run. Args: prev_calc_dir (str):
 Directory containing the outputs( vasprun.xml and OUTCAR) of previous vasp run. standardize (float):
 Whether to standardize to a primitive standard cell. Defaults to False. sym_prec (float):
 Tolerance for symmetry finding. If not 0, the final structure from the previous run will be symmetrized to get a primitive standard cell. Set to 0 if you don't want that. international_monoclinic (bool):
 Whether to use international convention (vs Curtarolo) for monoclinic. Defaults True. reciprocal_density (int):
 density of k-mesh by reciprocal volume (defaults to 100) small_gap_multiply ([float, float]):
 If the gap is less than 1st index, multiply the default reciprocal_density by the 2nd index. \\*\\*kwargs: All kwargs supported by MPStaticSet, other than prev_incar and prev_structure and prev_kpoints which are determined from the prev_calc_dir. """

        vasprun, outcar = get_vasprun_outcar(prev_calc_dir)

        prev_incar = vasprun.incar
        prev_kpoints = vasprun.kpoints

        if standardize:
            warnings.warn("Use of standardize=True with from_prev_run is not "
                          "recommended as there is no guarantee the copied "
                          "files will be appropriate for the standardized "
                          "structure. copy_chgcar is enforced to be false.")

        # We will make a standard structure for the given symprec.
        prev_structure = get_structure_from_prev_run(
            vasprun, outcar, sym_prec=standardize and sym_prec,
            international_monoclinic=international_monoclinic)

        # multiply the reciprocal density if needed:
        if small_gap_multiply:
            gap = vasprun.eigenvalue_band_properties[0]
            if gap <= small_gap_multiply[0]:
                reciprocal_density = reciprocal_density * small_gap_multiply[1]

        return cls(
            structure=prev_structure, prev_incar=prev_incar,
            prev_kpoints=prev_kpoints,
            reciprocal_density=reciprocal_density, **kwargs)