def _manifest(package_name):
    """
    Helper function to create an appropriate manifest with a provided package name.

    :pram package_name The package name used in the manifest file.
    """
    return """
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="{}" >

    <uses-sdk
            android:minSdkVersion="21"
            android:targetSdkVersion="29"/>
</manifest>
""".format(package_name)