Android OpenSans font family. More info here: https://developer.android.com/guide/topics/ui/look-and-feel/fonts-in-xml

opensans.xml

<?xml version="1.0" encoding="utf-8"?>
<font-family xmlns:android="http://schemas.android.com/apk/res/android">
    <font
            android:fontStyle="normal"
            android:fontWeight="300"
            android:font="@font/OpenSans_Light"/>
    
    <font
            android:fontStyle="italic"
            android:fontWeight="300"
            android:font="@font/OpenSans_LightItalic"/>

    <font
            android:fontStyle="normal"
            android:fontWeight="400"
            android:font="@font/OpenSans_Regular"/>

    <font
            android:fontStyle="italic"
            android:fontWeight="400"
            android:font="@font/OpenSans_Italic"/>
    <font
            android:fontStyle="normal"
            android:fontWeight="600"
            android:font="@font/OpenSans_SemiBold"/>
    <font
            android:fontStyle="italic"
            android:fontWeight="600"
            android:font="@font/OpenSans_SemiBoldItalic"/>
    <font
            android:fontStyle="normal"
            android:fontWeight="700"
            android:font="@font/OpenSans_Bold"/>
    <font
            android:fontStyle="normal"
            android:fontWeight="700"
            android:font="@font/OpenSans_BoldItalic"/>
    <font
            android:fontStyle="normal"
            android:fontWeight="800"
            android:font="@font/OpenSans_ExtraBold"/>
    <font
            android:fontStyle="italic"
            android:fontWeight="800"
            android:font="@font/OpenSans_ExtraBold"/>

</font-family>