Remove unnecessary extern-crate statements

Author: mre

Cargo.lock

@@ -2,12 +2,14 @@
 name = "profiling"
 version = "0.1.0"
 authors = ["Matthias Endler <matthias-endler@gmx.net>"]
+edition = "2018"
 
 [dependencies]
 # Disabling the default features makes pyo3 choose binary linking
 hyperjson = { path = "..", default-features = false }
 structopt = "0.3.2"
 clap = "2.33.0"
+serde_json = "1.0.40"
 
 [dependencies.pyo3]
 version = "0.8.0"

profiling/Cargo.toml

@@ -14,16 +14,11 @@
 //! callgrind_annotate --auto=yes callgrind.out.35583 >out.rs
 //! qcachegrind callgrind.out.35583
 //! ```
-extern crate structopt;
-#[macro_use]
-extern crate clap;
-
-extern crate hyperjson;
-extern crate pyo3;
 
 mod profiles;
 
 use structopt::StructOpt;
+use clap::arg_enum;
 
 arg_enum! {
     #[derive(Debug)]

profiling/src/main.rs

@@ -1,22 +1,16 @@
 #![feature(test)]
 
-#[macro_use]
-extern crate failure;
-#[macro_use]
-extern crate pyo3;
-extern crate serde;
-extern crate serde_derive;
-extern crate serde_json;
-extern crate test;
-
 use std::collections::BTreeMap;
 use std::fmt;
 use std::marker::PhantomData;
+use failure::Fail;
 
 use pyo3::prelude::*;
 use pyo3::exceptions::TypeError as PyTypeError;
 use pyo3::exceptions::ValueError as PyValueError;
 use pyo3::types::{PyDict, PyFloat, PyList, PyAny, PyTuple};
+use pyo3::{import_exception, wrap_pyfunction};
+
 use serde::de::{self, DeserializeSeed, Deserializer, MapAccess, SeqAccess, Visitor};
 use serde::ser::{self, Serialize, SerializeMap, SerializeSeq, Serializer};