How to use the cytoolz.dicttoolz.merge function in cytoolz

data = {k: source_data[k] for k in fields}
        timestamps = {k: source_ts[k] for k in fields}

        return {}, data, timestamps

    if fields:
        event_fields = set(d['data_keys'])
        selected_fields = set(filter(comp_re.match, event_fields))
        discard_fields = event_fields - selected_fields
    else:
        discard_fields = set()
        selected_fields = set(d['data_keys'])

    objs_config = d.get('configuration', {}).values()
    config_data = merge(obj_conf['data'] for obj_conf in objs_config)
    config_ts = merge(obj_conf['timestamps']
                      for obj_conf in objs_config)
    all_extra_data = {}
    all_extra_ts = {}
    all_extra_dk = {}
    if not no_fields_filter:
        for dt, ts in [(config_data, config_ts),
                       (start, defaultdict(lambda: start['time'])),
                       (stop, defaultdict(lambda: stop['time']))]:
            # Look in the descriptor, then start, then stop.
            l_dk, l_data, l_ts = _project_header_data(
                dt, ts, selected_fields, comp_re)
            all_extra_data.update(l_data)
            all_extra_ts.update(l_ts)
            selected_fields.update(l_data)
            all_extra_dk.update(l_dk)

fields = (set(filter(comp_re.match, source_data)) - selected_fields)
        data = {k: source_data[k] for k in fields}
        timestamps = {k: source_ts[k] for k in fields}

        return {}, data, timestamps

    if fields:
        event_fields = set(d['data_keys'])
        selected_fields = set(filter(comp_re.match, event_fields))
        discard_fields = event_fields - selected_fields
    else:
        discard_fields = set()
        selected_fields = set(d['data_keys'])

    objs_config = d.get('configuration', {}).values()
    config_data = merge(obj_conf['data'] for obj_conf in objs_config)
    config_ts = merge(obj_conf['timestamps']
                      for obj_conf in objs_config)
    all_extra_data = {}
    all_extra_ts = {}
    all_extra_dk = {}
    if not no_fields_filter:
        for dt, ts in [(config_data, config_ts),
                       (start, defaultdict(lambda: start['time'])),
                       (stop, defaultdict(lambda: stop['time']))]:
            # Look in the descriptor, then start, then stop.
            l_dk, l_data, l_ts = _project_header_data(
                dt, ts, selected_fields, comp_re)
            all_extra_data.update(l_data)
            all_extra_ts.update(l_ts)
            selected_fields.update(l_data)
            all_extra_dk.update(l_dk)

self._first_important_matches(matches))
        for match, value in relevant_matches_and_values:
            if not isinstance(value, Mapping):
                raise InvalidTypeError(self.name, value, match.source, value.__class__.__name__,
                                       self._type.__name__)

        # mapkeys with important matches
        def key_is_important(match, key):
            return match.valueflags(self).get(key) == ParameterFlag.final
        important_maps = tuple(dict((k, v)
                                    for k, v in iteritems(match_value)
                                    if key_is_important(match, k))
                               for match, match_value in relevant_matches_and_values)
        # dump all matches in a dict
        # then overwrite with important matches
        return merge(concatv((v for _, v in relevant_matches_and_values),
                             reversed(important_maps)))

data = {k: source_data[k] for k in fields}
        timestamps = {k: source_ts[k] for k in fields}

        return {}, data, timestamps

    if fields:
        event_fields = set(d['data_keys'])
        selected_fields = set(filter(comp_re.match, event_fields))
        discard_fields = event_fields - selected_fields
    else:
        discard_fields = set()
        selected_fields = set(d['data_keys'])

    objs_config = d.get('configuration', {}).values()
    config_data = merge(obj_conf['data'] for obj_conf in objs_config)
    config_ts = merge(obj_conf['timestamps']
                      for obj_conf in objs_config)
    all_extra_data = {}
    all_extra_ts = {}
    all_extra_dk = {}
    if not no_fields_filter:
        for dt, ts in [(config_data, config_ts),
                       (start, defaultdict(lambda: start['time'])),
                       (stop, defaultdict(lambda: stop['time']))]:
            # Look in the descriptor, then start, then stop.
            l_dk, l_data, l_ts = _project_header_data(
                dt, ts, selected_fields, comp_re)
            all_extra_data.update(l_data)
            all_extra_ts.update(l_ts)
            selected_fields.update(l_data)
            all_extra_dk.update(l_dk)

def _render_(self, template_name='base.html', **extra_args):
        repr_args = merge(self.configuration.copy(), extra_args)

        if self.configuration['visualization_js']:
            repr_args['visualization_js'] = env.get_template(self.configuration['visualization_js']).render(**repr_args)
        else:
            raise Exception('Empty Visualization code!')

        if 'functions_js' in self.configuration and self.configuration['functions_js'] is not None:
            repr_args['functions_js'] = env.get_template(self.configuration['functions_js']).render(**repr_args)

        template = env.get_template(template_name)

        if not 'figure_id' in repr_args or not repr_args['figure_id']:
            repr_args['figure_id'] = 'fig-{0}'.format(uuid.uuid4())

        if not 'vis_uuid' in repr_args or not repr_args['vis_uuid']:
            repr_args['vis_uuid'] = 'datagram-vis-{0}'.format(uuid.uuid4())