title: Instance of 'Future<String>' instead of showing the value
body: <p>Iam using flutter and I am trying to get a value from shared_preferences that I had set before, and display it in a text widget. but i get Instance of <code>Future&lt;String&gt;</code> instead of the value. here is my code:</p>
  <pre><code>Future&lt;String&gt; getPhone() async {
      final SharedPreferences prefs = await SharedPreferences.getInstance();
      final String patientPhone = prefs.getString('patientPhone').toString();
          print(patientPhone);
  
      return patientPhone;
    }
  
  Future&lt;String&gt; phoneOfPatient = getPhone();
  
  Center(child: Text('${phoneOfPatient}'),))
  </code></pre>