A quick search for long drop down select menu

Hey,

Currently I have a list of 900 companies which each have a code associated with them.

Now im my application has to select a company.At the moment these are listed in the drop down menu but ofcourse it is very long.

What the user requested was a quick search where they could enter the name or code of the company and this then selected the required company from the drop down ?

Any ideas
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