How to compile OpenWrt PR from GitHub?

I want to compile this pull request
I had tried:

/openwrt$ git checkout 1635
error: short SHA1 1635 is ambiguous
hint: The candidates are:
hint:   1635025522 blob
hint:   16350a3875 blob
hint:   16352c713b tree
hint:   16354a5567 tree
hint:   163580af95 blob
hint:   163582f3be tree
hint:   16359943b7 tree
hint:   1635cd5f7c tree
error: pathspec '1635' did not match any file(s) known to git.

What's the right command to checkout a pull request?

Download it as a patch and apply:

patch -p 1 -i 1635.patch

(Assuming that you are in the root of the build system, for an OpenWrt main source PR. For a packages feed PR you would need to first cd into feeds/packages )


Thank You ,patch was applied successful, building now..