Place inside <head>:
<script src="https://robopostcodes.com/cdn/robopostcodes-typeahead-2.0.min.js">
</script>
Place after </form>:
<script>
roboPostcodes.typeahead('typeahead-postcode','postcode','[ YOUR API KEY ]');
roboPostcodes.typeahead('typeahead-town-or-city','town_or_city','[ YOUR API KEY ]');
roboPostcodes.typeahead('typeahead-county','county','[ YOUR API KEY ]');
roboPostcodes.typeahead('typeahead-country','country','[ YOUR API KEY ]');
</script>
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