Debian Font Configuration Warning

I’ve been learning to develop GUI applications for Debian with PyQt4 these days. When I ran the program in shell, two annoying warnings showed up.

Fontconfig warning: "/etc/fonts/conf.d/65-droid-sans-fonts.conf", line 103: Having multiple values in <test> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/65-droid-sans-fonts.conf", line 138: Having multiple values in <test> isn't supported and may not work as expected

As the warning messages hinted, to get rid of them I should convert multiple values in one <test> into multiple <test> tags, each of which only has one value. So I edited the file /etc/fonts/conf.d/65-droid-sans-fonts.conf.

Before

<test name="lang">
    <string>zh-cn</string>
    <string>zh-sg</string>
    <string>zh-hk</string>
    <string>zh-tw</string>
</test>

After

<test name="lang">
    <string>zh-cn</string>
</test>
<test name="lang">
    <string>zh-sg</string>
</test>
<test name="lang">
    <string>zh-hk</string>
</test>
<test name="lang">
    <string>zh-tw</string>
</test>