Can we add type definition

[viraths]

Can you please add type definition, so that we can use this library in typescript as well. Thanks you.

[zackargyle]

Hi! This is not something I am in need of and so will not be adding, but would be happy to review a Pull Request if you'd be up for contributing!

[andreiho]

DefinitelyTyped/DefinitelyTyped#28421