def METHOD_NAME(self, username=None):
    userdetails = self.run_function("user.info", [username])
    user_ssh_dir = os.path.join(userdetails["home"], ".ssh")
    authorized_keys_file = os.path.join(user_ssh_dir, "authorized_keys")
    key_fname = "issue_10198.id_rsa.pub"
    key_contents = (
        "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAAAgQC3dd5ACsvJhnIOrn6bSOkX5"
        "KyVDpTYsVAaJj3AmEo6Fr5cHXJFJoJS+Ld8K5vCscPzuXashdYUdrhL1E5Liz"
        "bza+zneQ5AkJ7sn2NXymD6Bbra+infO4NgnQXbGMp/NyY65jbQGqJeQ081iEV"
        f"YbDP2zXp6fmrqqmFCaakZfGRbVw== {username}\n"
    )
    # Create the keyfile that we expect to get back on the state call
    with salt.utils.files.fopen(
        os.path.join(RUNTIME_VARS.TMP_PRODENV_STATE_TREE, key_fname), "w"
    ) as kfh:
        kfh.write(key_contents)
    # Create a bogus key file on base environment
    with salt.utils.files.fopen(
        os.path.join(RUNTIME_VARS.TMP_STATE_TREE, key_fname), "w"
    ) as kfh:
        kfh.write(
            "ssh-rsa A!AAB3NzaC1yc2EAAAADAQABAAAAgQC3dd5ACsvJhnIOrn6bSOkX5"
            "KyVDpTYsVAaJj3AmEo6Fr5cHXJFJoJS+Ld8K5vCscPzuXashdYUdrhL1E5Liz"
            "bza+zneQ5AkJ7sn2NXymD6Bbra+infO4NgnQXbGMp/NyY65jbQGqJeQ081iEV"
            f"YbDP2zXp6fmrqqmFCaakZfGRbVw== {username}\n"
        )
    ret = self.run_state(
        "ssh_auth.present",
        name="Setup Keys",
        source=f"salt://{key_fname}?saltenv=prod",
        enc="ssh-rsa",
        user=username,
        comment=username,
    )
    self.assertSaltTrueReturn(ret)
    with salt.utils.files.fopen(authorized_keys_file, "r") as fhr:
        self.assertEqual(fhr.read(), key_contents)
    os.unlink(authorized_keys_file)
    ret = self.run_state(
        "ssh_auth.present",
        name="Setup Keys",
        source=f"salt://{key_fname}",
        enc="ssh-rsa",
        user=username,
        comment=username,
        saltenv="prod",
    )
    self.assertSaltTrueReturn(ret)
    with salt.utils.files.fopen(authorized_keys_file, "r") as fhr:
        self.assertEqual(fhr.read(), key_contents)