add itertools dependency

Cargo.lock

@@ -2,11 +2,18 @@
 # It is not intended for manual editing.
 version = 4
 
+[[package]]
+name = "either"
+version = "1.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "48c757948c5ede0e46177b7add2e67155f70e33c07fea8284df6576da70b3719"
+
 [[package]]
 name = "gentoo-utils"
 version = "0.1.0"
 dependencies = [
  "get",
+ "itertools",
  "mon",
 ]
 
@@ -19,6 +26,15 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "itertools"
+version = "0.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2b192c782037fadd9cfa75548310488aabdbf3d2da73885b31bd0abd03351285"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "mon"
 version = "0.1.0"