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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 dump(self, fname=None, overwrite=True, include_keys=None, exclude_keys=['project.plotters'], include_descriptions=True, **kwargs):
 """Dump this instance to a yaml file Parameters fname: str or None file name to write to. If None, the string that would be written to a file is returned overwrite: bool If True and `fname` already exists, it will be overwritten include_keys: None or list of str Keys in the dictionary to be included. If None, all keys are included exclude_keys: list of str Keys from the :class:`RcParams` instance to be excluded Other Parameters ``**kwargs`` Any other parameter for the :func:`yaml.dump` function Returns ------- str or None if fname is ``None``, the string is returned. Otherwise, ``None`` is returned Raises ------ IOError If `fname` already exists and `overwrite` is False See Also -------- load_from_file"""

        if fname is not None and not overwrite and os.path.exists(fname):
            raise IOError(
                '%s already exists! Set overwrite=True to overwrite it!' % (
                    fname))
        if six.PY2:
            kwargs.setdefault('encoding', 'utf-8')
        d = {key: val for key, val in six.iteritems(self) if (
                include_keys is None or key in include_keys) and
             key not in exclude_keys}
        kwargs['default_flow_style'] = False
        if include_descriptions:
            s = yaml.dump(d, **kwargs)
            desc = self.descriptions
            i = 2
            header = self.HEADER.splitlines() + [
                '', 'Created with python', ''] + sys.version.splitlines() + [
                    '', '']
            lines = ['# ' + l for l in header] + s.splitlines()
            for l in lines[2:]:
                key = l.split(':')[0]
                if key in desc:
                    lines.insert(i, '# ' + '\n# '.join(desc[key].splitlines()))
                    i += 1
                i += 1
            s = '\n'.join(lines)
            if fname is None:
                return s
            else:
                with open(fname, 'w') as f:
                    f.write(s)
        else:
            if fname is None:
                return yaml.dump(d, **kwargs)
            with open(fname, 'w') as f:
                yaml.dump(d, f, **kwargs)
        return None