How to create function that get value from Promise.prototype.then()

Question

I want to create function that get value from Promise.prototype.then(), but I don't exactly know how it's works.

I have such code:

ConfigurationPage.filteredItems.getText().then(function(value){console.log(value)});

and in console log I get some value - it's OK.

I try to create function that looks like this:

function getValue(data) {
return data.then(function(value){value})}

My expected result when I call such function:

getValue(ConfigurationPage.filteredItems.getText())

I get a value.

But I don't know how to create right function.

Thanks for support.