diff --git a/Cargo.lock b/Cargo.lock
index 8cebab4ed..a3879ee02 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -309,7 +309,7 @@ dependencies = [
  "secp256k1 0.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.117 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.117 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.59 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "shiplift 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "structopt 0.3.20 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempfile 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -479,7 +479,7 @@ dependencies = [
  "ethereum-types 0.9.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-hex 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.117 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.59 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "tiny-keccak 1.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "uint 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1025,7 +1025,7 @@ dependencies = [
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.117 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.117 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.59 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.62 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1677,7 +1677,7 @@ dependencies = [
  "percent-encoding 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "pin-project-lite 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.117 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.59 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_urlencoded 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "tokio 0.2.22 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1835,7 +1835,7 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.59"
+version = "1.0.62"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "itoa 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1883,7 +1883,7 @@ dependencies = [
  "mime 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "openssl 0.10.26 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.117 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.59 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "tar 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "tokio 0.1.22 (registry+https://github.com/rust-lang/crates.io-index)",
  "tokio-codec 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2500,7 +2500,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.117 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.59 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasm-bindgen-macro 0.2.56 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -2602,7 +2602,7 @@ dependencies = [
  "rustc-hex 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "secp256k1 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.117 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.59 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "tiny-keccak 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -2884,7 +2884,7 @@ dependencies = [
 "checksum serde-rlp 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "69472f967577700225f282233c0625f7b73c371c3953b72d6dcfb91bd0133ca9"
 "checksum serde_bytes 0.11.4 (registry+https://github.com/rust-lang/crates.io-index)" = "3bf487fbf5c6239d7ea2ff8b10cb6b811cd4b5080d1c2aeed1dec18753c06e10"
 "checksum serde_derive 1.0.117 (registry+https://github.com/rust-lang/crates.io-index)" = "cbd1ae72adb44aab48f325a02444a5fc079349a8d804c1fc922aed3f7454c74e"
-"checksum serde_json 1.0.59 (registry+https://github.com/rust-lang/crates.io-index)" = "dcac07dbffa1c65e7f816ab9eba78eb142c6d44410f4eeba1e26e4f5dfa56b95"
+"checksum serde_json 1.0.62 (registry+https://github.com/rust-lang/crates.io-index)" = "ea1c6153794552ea7cf7cf63b1231a25de00ec90db326ba6264440fa08e31486"
 "checksum serde_urlencoded 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9ec5d77e2d4c73717816afac02670d5c4f534ea95ed430442cad02e7a6e32c97"
 "checksum sha3 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "f81199417d4e5de3f04b1e871023acea7389672c4135918f05aa9cbf2f2fa809"
 "checksum shiplift 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b78521d24224ac77e489f92efa0f02884e7fc2973f97b2e72c9bb3e4771e6f6b"