namespace Microsoft.Extensions.Configuration
{
    /// <summary>
    /// Static helper class that allows binding strongly typed objects to configuration values.
    /// </summary>
    public static class [ConfigurationBinder]
    {
    
        ...
    
        /// <summary>
        /// Extracts the value with the specified key and converts it to type T.
        /// </summary>
        /// <typeparam name="T">The type to convert the value to.</typeparam>
        /// <param name="configuration">The configuration.</param>
        /// <param name="key">The key of the configuration section's value to convert.</param>
        /// <param name="defaultValue">The default value to use if no value is found.</param>
        /// <returns>The converted value.</returns>
        public static T? GetValue<T>(this IConfiguration configuration, string key, T defaultValue)
        {
            return (T?)GetValue(configuration, typeof(T), key, defaultValue);
        }