Accessing Telerik Silverlight RadGridView from Button on Group header - silverlight

Question

I have a RadGridView, that groups its contents.
I have a Button on the group header
When I click on the button (btnSave) I would like to get access to the group to read the group key.
What can I put in the Click of btnSave to accomplish this?
<telerik:RadGridView x:Name="grdNotams" Grid.Row="1" AutoGenerateColumns="False" RowIndicatorVisibility="Collapsed" ShowGroupPanel="False">
<telerik:RadGridView.Columns>
<telerik:GridViewDataColumn UniqueName="colNewStatus" DataMemberBinding="{Binding NewStatus}" Header="New Status" IsFilterable="False" IsSortable="False">
<telerik:GridViewDataColumn.CellTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<telerik:RadRadioButton Content="C" Width="30" IsChecked="{Binding NewStatus, Mode=TwoWay, Converter={StaticResource StringToBooleanConverter},ConverterParameter=C}" GroupName="{Binding RadioButtonName}"/>
<telerik:RadRadioButton Content="M" Width="30" Margin="5,0,0,0" IsChecked="{Binding NewStatus, Mode=TwoWay, Converter={StaticResource StringToBooleanConverter},ConverterParameter=M}" GroupName="{Binding RadioButtonName}"/>
<telerik:RadRadioButton Content="I" Width="30" Margin="5,0,0,0" IsChecked="{Binding NewStatus, Mode=TwoWay, Converter={StaticResource StringToBooleanConverter},ConverterParameter=I}" GroupName="{Binding RadioButtonName}"/>
</StackPanel>
</DataTemplate>
</telerik:GridViewDataColumn.CellTemplate>
</telerik:GridViewDataColumn>
<telerik:GridViewDataColumn Header="Status" UniqueName="colStatus" DataMemberBinding="{Binding Model.Status, Converter={StaticResource StatusConverter}}" HeaderTextAlignment="Center" TextAlignment="Center" IsFilterable="False" IsSortable="False"/>
<telerik:GridViewDataColumn Header="Trip #" UniqueName="colTripNumber" DataMemberBinding="{Binding Model.TripNumber}" HeaderTextAlignment="Center" TextAlignment="Center" IsFilterable="False" IsSortable="False"/>
<telerik:GridViewDataColumn Header="Date" UniqueName="colDate" DataMemberBinding="{Binding Model.DepartureTime}" DataFormatString="d" HeaderTextAlignment="Center" TextAlignment="Center" IsFilterable="False" IsSortable="False"/>
</telerik:RadGridView.Columns>
<telerik:RadGridView.GroupHeaderTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<telerik:RadButton x:Name="btnSave" Click="btnSave_Click">
<StackPanel Orientation="Vertical">
<Image Source="../images/save.jpg" Height="30" Width="30" HorizontalAlignment="Center"/>
<TextBlock TextAlignment="Center" TextWrapping="Wrap">Update</TextBlock>
</StackPanel>
</telerik:RadButton>
<TextBlock Text="{Binding Group.Key}" FontSize="14" FontWeight="Bold" FontStyle="{Binding EarliestNotamDepartureTime, Converter={StaticResource DateTimeToItalicsConverter}}" TextWrapping="Wrap" VerticalAlignment="Center" Padding="5"/>
</StackPanel>
</DataTemplate>
</telerik:RadGridView.GroupHeaderTemplate>
<telerik:RadGridView.GroupDescriptors>
<telerik:GroupDescriptor Member="NotamGroup" >
</telerik:GroupDescriptor>
<telerik:GroupDescriptor Member="Model.NotamText">
</telerik:GroupDescriptor>
</telerik:RadGridView.GroupDescriptors>
</telerik:RadGridView>

Answer 1

Figured it out.
The DataContext has the information I needed in the form of the GroupViewModel class.
Code
private void btnSave_Click(object sender, RoutedEventArgs e)
{
GroupViewModel vm = ((RadButton)sender).DataContext as GroupViewModel;
}