title: How to change responsive breakpoint values in MUI theme?
body: <p>I'm using the v1 beta of MUI. The media query breakpoints are not the same as Bootstrap v4 breakpoints I'm using and I wanted to override the values of the MUI breakpoints to match that of Bootstraps.</p>
  <p>I need to do something like below but I'm not finding enough documentation to get it to work.</p>
  <p><strong>Current error is:</strong></p>
  <blockquote>
  <p>&quot;Uncaught TypeError: Object(...) is not a function&quot; when trying to
  reference createBreakpoints() as a function.</p>
  </blockquote>
  <pre><code>import { MuiThemeProvider, createMuiTheme, createBreakpoints } from &quot;material-ui/styles&quot;;
      
  const breakpointValues = {
    xs: 0,
    sm: 576,
    md: 768,
    lg: 992,
    xl: 1200,
  };
  
  const breakpoints = createBreakpoints({ values: breakpointValues });
  const theme = createMuiTheme({ breakpoints });
  </code></pre>
  <pre><code>&lt;MuiThemeProvider theme={theme}&gt;
    &lt;App /&gt;
  &lt;/MuiThemeProvider&gt;
  </code></pre>