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diff --git a/src/app/pipes/map.pipe.ts b/src/app/pipes/map.pipe.ts
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+/*
+ * Copyright (c) 2022. Deutsche Telekom AG
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+
+import { Pipe, PipeTransform } from '@angular/core';
+
+@Pipe({
+  name: 'map',
+  pure: false
+})
+/*
+  MapPipe allows us to run a function in a template
+  for example, you need to filter out some elements from the array before displaying these elements. You can call a function for getting filtered array
+  directly from template, but this function will be triggered everytime when user interacts with page.
+  MapPipe allows you to call a function through this pipe, so function will be called only when necessary.
+  Usage:
+    we have function in .ts file that's called filterZeroValues
+    in template we can use this function:
+    *ngFor="let item in elements | map : filterZeroValues"
+    where the first parameter of map pipe is function to be called, and other parameters will be passed as arguments to this function
+    Important note: as you can see from implementation, elements array will be passed to your function as a first argument
+*/
+export class MapPipe implements PipeTransform {
+
+  transform<T, R>(
+    thisArg: T,
+    project: (t:T, ...others: any[]) => R,
+    ...args: any[]
+  ): R {
+    return project(thisArg, ...args);
+  }
+
+}