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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 calibrate(filename):
 """ Append the calibration parameters as variables of the netcdf file. Keyword arguments: filename -- the name of a netcdf file. """

    params = calibration_to(filename)
    with nc.loader(filename) as root:
        for key, value in params.items():
            nc.getdim(root, 'xc_1', 1)
            nc.getdim(root, 'yc_1', 1)
            if isinstance(value, list):
                for i in range(len(value)):
                    nc.getvar(root, '%s_%i' % (key, i), 'f4', ('time', 'yc_1', 'xc_1' ))[:] = value[i]
            else:
                nc.getvar(root, key, 'f4', ('time', 'yc_1', 'xc_1'))[:] = value