Multipart.lookup: def of bend-kit-multipart@0.3.0.0
Import: import bend-kit-multipart@0.3.0.0/multipart.bend as Multipart
Lines 133-139 of bend-kit-multipart@0.3.0.0/multipart.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-multipart@0.3.0.0/multipart.bend&start_line=133&end_line=139

import Base

# The first parameter named k (lowercase).
def lookup(xs: List<&2, Param>, +k: String) -> Maybe<&2, String>:
  match xs:
    case Nil{}:
      None{}
    case Con{Param{+k2, +v}, t}:
      Bool.pick(Maybe<&2, String>, String.eq(k2, k), Some{v}, lookup(t, k))

Uses (6):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.pick
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String.eq
  https://jend.leeeet.dev/definition.txt?path=bend-kit-multipart@0.3.0.0/multipart.bend&name=Param