How to install / parse build dependencies from debian/control?

Let's suppose you downloaded a source code folder, that contains an existing /debian/ folder as well as /debian/control file.

Let's suppose the package in question is not in Debian official repository, so apt-get build-dep cannot be used.

How to parse the Build-Depends: line?

For example, if the line would read Build-Depends: debhelper (>= 8), faketime, is there some tool control-parse debian/control build-depends that would echo debhelper faketime?

Especially when it's multi line?

Are there existing Debian tools or has one to write its own code to parse this?