diff --git a/Cargo.lock b/Cargo.lock
index 7cb74a5..4d1dace 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,5 +1,7 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
+version = 3
+
 [[package]]
 name = "ansi_term"
 version = "0.11.0"
@@ -916,9 +918,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro-hack"
-version = "0.5.18"
+version = "0.5.20+deprecated"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "99c605b9a0adc77b7211c6b1f722dcb613d68d66859a44f3d485a6da332b0598"
+checksum = "dc375e1527247fe1a97d8b7156678dfe7c1af2fc075c9a4db3690ecd2a148068"
 
 [[package]]
 name = "proc-macro-nested"