Добавьте файлы проекта.

TestApp02/Data/WeatherForecast.cs

@@ -0,0 +1,13 @@
+namespace TestApp02.Data
+{
+    public class WeatherForecast
+    {
+        public DateTime Date { get; set; }
+
+        public int TemperatureC { get; set; }
+
+        public int TemperatureF => 32 + (int)(TemperatureC / 0.5556);
+
+        public string? Summary { get; set; }
+    }
+}

TestApp02/Data/WeatherForecastService.cs

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+namespace TestApp02.Data
+{
+    public class WeatherForecastService
+    {
+        private static readonly string[] Summaries = new[]
+        {
+            "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
+        };
+
+        public Task<WeatherForecast[]> GetForecastAsync(DateTime startDate)
+        {
+            var rng = new Random();
+            return Task.FromResult(Enumerable.Range(1, 5).Select(index => new WeatherForecast
+            {
+                Date = startDate.AddDays(index),
+                TemperatureC = rng.Next(-20, 55),
+                Summary = Summaries[rng.Next(Summaries.Length)]
+            }).ToArray());
+        }
+    }
+}