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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 to_xyz(self, buf=None, sort_index=True, index=False, header=False, float_format='{:.6f}'.format, overwrite=True):
 """Write xyz-file Args: buf (str):
 StringIO-like, optional buffer to write to sort_index (bool):
 If sort_index is true, the :class:`~chemcoord.Cartesian` is sorted by the index before writing. float_format (one-parameter function):
 Formatter function to apply to column’s elements if they are floats. The result of this function must be a unicode string. overwrite (bool):
 May overwrite existing files. Returns: formatted : string (or unicode, depending on data and options) """

        if sort_index:
            molecule_string = self.sort_index().to_string(
                header=header, index=index, float_format=float_format)
        else:
            molecule_string = self.to_string(header=header, index=index,
                                             float_format=float_format)

        # NOTE the following might be removed in the future
        # introduced because of formatting bug in pandas
        # See https://github.com/pandas-dev/pandas/issues/13032
        space = ' ' * (self.loc[:, 'atom'].str.len().max()
                       - len(self.iloc[0, 0]))

        output = '{n}\n{message}\n{alignment}{frame_string}'.format(
            n=len(self), alignment=space, frame_string=molecule_string,
            message='Created by chemcoord http://chemcoord.readthedocs.io/')

        if buf is not None:
            if overwrite:
                with open(buf, mode='w') as f:
                    f.write(output)
            else:
                with open(buf, mode='x') as f:
                    f.write(output)
        else:
            return output