Update package(s) (in an environment) by name.

def update(self, *pkgs, **kwargs):
        """Update package(s) (in an environment) by name."""
        cmd_list = ['update', '--json', '--yes']

        if not pkgs and not kwargs.get('all'):
            raise TypeError("Must specify at least one package to update, or "
                            "all=True.")

        cmd_list.extend(
            self._setup_install_commands_from_kwargs(
                kwargs,
                ('dry_run', 'no_deps', 'override_channels',
                 'no_pin', 'force', 'all', 'use_index_cache', 'use_local',
                 'alt_hint')))

        cmd_list.extend(pkgs)

        return self._call_and_parse(cmd_list, abspath=kwargs.get('abspath',
                                                                 True))