diff --git a/.appveyor.yml b/.appveyor.yml
index 8aa2515..bb515f1 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -4,7 +4,7 @@ install:
   - "SET PATH=%PYTHON%;%PYTHON%\\Scripts;%PATH%"
   - "python --version"
   - appveyor DownloadFile https://win.rustup.rs/ -FileName rustup-init.exe
-  - rustup-init -yv --default-toolchain nightly-2019-02-07 --default-host x86_64-pc-windows-msvc
+  - rustup-init -yv --default-toolchain nightly-2019-07-19 --default-host x86_64-pc-windows-msvc
   - set PATH=%PATH%;%USERPROFILE%\.cargo\bin
   - rustc -V
   - cargo -V
diff --git a/.travis.yml b/.travis.yml
index 0590974..53b251f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -15,14 +15,14 @@ matrix:
   fast_finish: true
   include:
     - os: linux
-      rust: nightly-2019-02-07
+      rust: nightly-2019-07-19
     - if: tag IS present
       os: osx
       osx_image: xcode9.4
-      rust: nightly-2019-02-07
+      rust: nightly-2019-07-19
     - os: osx
       osx_image: xcode10.1
-      rust: nightly-2019-02-07
+      rust: nightly-2019-07-19
 
 install:
   - |
@@ -38,7 +38,7 @@ install:
       pip install cffi virtualenv pytest numpy
     fi
   - cargo install --git https://github.com/PyO3/pyo3-pack.git --tag v0.6.1 pyo3-pack
-  - rustup default nightly-2019-02-07
+  - rustup default nightly-2019-07-19
   - rustup component add rustfmt
 
 script:
diff --git a/Cargo.lock b/Cargo.lock
index 4df51da..8751ce9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,7 +2,7 @@
 # It is not intended for manual editing.
 [[package]]
 name = "aho-corasick"
-version = "0.7.4"
+version = "0.7.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -28,7 +28,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "backtrace-sys 0.1.31 (registry+https://github.com/rust-lang/crates.io-index)",
  "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-demangle 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -38,7 +38,7 @@ version = "0.1.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cc 1.0.38 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -156,7 +156,7 @@ dependencies = [
  "rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_xorshift 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "reductive 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.91 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
  "toml 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -167,10 +167,10 @@ dependencies = [
  "failure 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "finalfusion 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "ndarray 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "numpy 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "pyo3 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "numpy 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pyo3 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "toml 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -194,24 +194,45 @@ dependencies = [
  "syn 0.15.42 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "indoc"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "indoc-impl 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro-hack 0.5.9 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "indoc-impl"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro-hack 0.5.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unindent 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "inventory"
-version = "0.1.3"
+version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "ctor 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "ghost 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "inventory-impl 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "inventory-impl 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "inventory-impl"
-version = "0.1.3"
+version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.42 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -230,6 +251,11 @@ dependencies = [
  "either 1.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "itoa"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "lazy_static"
 version = "1.3.0"
@@ -237,7 +263,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "libc"
-version = "0.2.60"
+version = "0.2.62"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -248,24 +274,6 @@ dependencies = [
  "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "mashup"
-version = "0.1.9"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "mashup-impl 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro-hack 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "mashup-impl"
-version = "0.1.9"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "proc-macro-hack 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "matrixmultiply"
 version = "0.1.15"
@@ -284,7 +292,7 @@ name = "memmap"
 version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -340,20 +348,20 @@ name = "num_cpus"
 version = "1.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "numpy"
-version = "0.6.0"
+version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "ndarray 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-complex 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "pyo3 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pyo3 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -365,17 +373,34 @@ dependencies = [
 ]
 
 [[package]]
-name = "proc-macro-hack"
-version = "0.4.2"
+name = "paste"
+version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro-hack-impl 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "paste-impl 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro-hack 0.5.9 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
-name = "proc-macro-hack-impl"
-version = "0.4.2"
+name = "paste-impl"
+version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro-hack 0.5.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "proc-macro-hack"
+version = "0.5.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "proc-macro2"
@@ -385,40 +410,52 @@ dependencies = [
  "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "proc-macro2"
+version = "1.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "pyo3"
-version = "0.7.0"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "inventory 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
- "mashup 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "indoc 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "inventory 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "pyo3cls 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "spin 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "version_check 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "paste 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pyo3cls 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)",
+ "spin 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unindent 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "pyo3-derive-backend"
-version = "0.7.0"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.42 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "pyo3cls"
-version = "0.7.0"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
- "pyo3-derive-backend 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.42 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pyo3-derive-backend 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -429,13 +466,21 @@ dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "quote"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "rand"
 version = "0.6.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "autocfg 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -490,7 +535,7 @@ name = "rand_jitter"
 version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -502,7 +547,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "fuchsia-cprng 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -577,29 +622,30 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.2.0"
+version = "1.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "aho-corasick 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "aho-corasick 0.7.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex-syntax 0.6.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex-syntax 0.6.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "utf8-ranges 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "regex-syntax"
-version = "0.6.10"
+version = "0.6.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "ucd-util 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
-]
 
 [[package]]
 name = "rustc-demangle"
 version = "0.1.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "ryu"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "scopeguard"
 version = "0.3.3"
@@ -607,7 +653,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "serde"
-version = "1.0.91"
+version = "1.0.99"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "serde_derive 1.0.98 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -623,9 +669,19 @@ dependencies = [
  "syn 0.15.42 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "serde_json"
+version = "1.0.40"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "itoa 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ryu 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "spin"
-version = "0.5.0"
+version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -638,6 +694,16 @@ dependencies = [
  "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "syn"
+version = "1.0.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "synstructure"
 version = "0.10.2"
@@ -662,27 +728,27 @@ name = "toml"
 version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "serde 1.0.91 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
-name = "ucd-util"
-version = "0.1.5"
+name = "unicode-xid"
+version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "unicode-xid"
-version = "0.1.0"
+version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "utf8-ranges"
-version = "1.0.3"
+name = "unindent"
+version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "version_check"
-version = "0.1.5"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -705,7 +771,7 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
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@@ -746,15 +813,18 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
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@@ -770,21 +840,24 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
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-"checksum regex-syntax 0.6.10 (registry+https://github.com/rust-lang/crates.io-index)" = "cd5485bf1523a9ed51c4964273f22f63f24e31632adb5dad134f488f86a3875c"
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diff --git a/Cargo.toml b/Cargo.toml
index 0eeabf0..57da83c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,7 +15,7 @@ name = "finalfusion"
 crate-type = ["cdylib"]
 
 [dependencies.pyo3]
-version = "0.7"
+version = "0.8"
 features = ["extension-module"]
 
 [dependencies]
@@ -24,5 +24,5 @@ failure = "0.1"
 finalfusion = "0.9"
 libc = "0.2"
 ndarray = "0.12"
-numpy = "0.6"
+numpy = "0.7"
 toml = "0.5"
diff --git a/src/embeddings.rs b/src/embeddings.rs
index 5301543..e39fe29 100644
--- a/src/embeddings.rs
+++ b/src/embeddings.rs
@@ -374,13 +374,13 @@ impl PyEmbeddings {
     ) -> PyResult<Vec<PyObject>> {
         let mut r = Vec::with_capacity(results.len());
         for ws in results {
-            r.push(
+            r.push(IntoPy::into_py(
                 Py::new(
                     py,
                     PyWordSimilarity::new(ws.word.to_owned(), ws.similarity.into_inner()),
-                )?
-                .into_object(py),
-            )
+                )?,
+                py,
+            ))
         }
         Ok(r)
     }
@@ -406,8 +406,10 @@ impl PyIterProtocol for PyEmbeddings {
     fn __iter__(slf: PyRefMut<Self>) -> PyResult<PyObject> {
         let gil = Python::acquire_gil();
         let py = gil.python();
-        let iter =
-            Py::new(py, PyEmbeddingIterator::new(slf.embeddings.clone(), 0))?.into_object(py);
+        let iter = IntoPy::into_py(
+            Py::new(py, PyEmbeddingIterator::new(slf.embeddings.clone(), 0))?,
+            py,
+        );
 
         Ok(iter)
     }