title: Why am I getting this error?pipe is not a function
body: <p>This returns the dropdown options available to be displayed. I'm assuming the problem is with the .pipe but I can't seem to correct it.</p>
  <pre><code>        return this.lasService.getLasDropDownOptions(true)
            .pipe(takeUntil(this.unsubscribe))
            .subscribe((lasOptions) =&gt; {
              return resolve(lasOptions.map((option) =&gt; {
                return option || [];
              }));
            });
        }
     
  
   getLasDropDownOptions(refresh) {
      return this.getLasData(refresh)
        .pipe(takeUntil(this.unsubscribe))
        .subscribe((response) =&gt; {
          return response.map((las) =&gt; {
            las.displayValue = las.name + ' - ' + las.expression;
            if (!las.status) {
              las.disabled = true;
              las.category = 'Calculating';
            } else {
              las.category = las.longterm ? 'Online Range' : 'Short Term';
            }
            return las;
          });
        });
    } ```
  </code></pre>