Question: I have a .txt textfile with a list formatted like 
`[' ok ', ' test ', ' help ']`
How can I read/import this textfile list into a python list?

Answer: 
color: yellow; does not overwrite the class (mat-tooltip) you have to add !important;

like this:

**XX.component.ts:**

```
import { Component, OnInit } from '@angular/core';
import { ViewEncapsulation } from '@angular/core';

@Component({
  selector: 'app-tooltip-demo',
  templateUrl: './XX.component.html',
  styleUrls: ['./XX.component.css'],
  encapsulation: ViewEncapsulation.None
})
export class TooltipDemoComponent implements OnInit {

  constructor() { }

  ngOnInit() {
  }
}

```

**HTML Template:**

```
<div matTooltip="This is the Tooltip!" matTooltipPosition="below">This text has a tooltip!</div>

```

**CSS Template:**

```
.mat-tooltip {
  color: yellow !important;
}

```

then it will work !
Late at the party :-| Just in case somebody has as well the troubles. Angular Material won't apply the class if its encapsulated. The solution?

Put the style in the `styles.scss` file and using `!important`. This finally solved my problem. e.g.

```
.red-tooltip {
    background-color: red !important;
    font-size: larger !important;
}

```