title: ERROR installing web3[tester]: Failed building wheel for blake2b-py
body: <p>I'm trying to install the web3 tester with <code>pip install -U web3[tester]</code> but always getting this error.</p>
  <p>Pip and setuptools are both on their current version.</p>
  <p>The complete error:</p>
  <pre><code>Building wheels for collected packages: blake2b-py
    Building wheel for blake2b-py (PEP 517) ... error
    ERROR: Command errored out with exit status 1:
     command: /Library/Frameworks/Python.framework/Versions/3.9/bin/python3.9 /Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/pep517/_in_process.py build_wheel /var/folders/rf/h_h1jw411_l1d366hm2pybm00000gn/T/tmpigyl8c27
         cwd: /private/var/folders/rf/h_h1jw411_l1d366hm2pybm00000gn/T/pip-install-yu97ljpj/blake2b-py_61e5c1e928bf4c3fa77c17397812b60f
    Complete output (20 lines):
       Compiling proc-macro2 v1.0.24
       Compiling unicode-xid v0.2.1
       Compiling syn v1.0.58
       Compiling proc-macro-hack v0.5.19
       Compiling memchr v2.3.4
       Compiling serde_derive v1.0.118
       Compiling serde v1.0.118
       Compiling ryu v1.0.5
       Compiling lazy_static v1.4.0
       Compiling serde_json v1.0.61
    error: could not compile `ryu`
    
    To learn more, run the command again with --verbose.
    warning: build failed, waiting for other jobs to finish...
    error: build failed
     maturin failed
      Caused by: Failed to build a native library through cargo
      Caused by: Cargo build finished with &quot;exit code: 101&quot;: `cargo rustc --message-format json --manifest-path Cargo.toml --lib --release -- -C link-arg=-undefined -C link-arg=dynamic_lookup`
    Running `maturin pep517 build-wheel -i python`
    Error: Command '['maturin', 'pep517', 'build-wheel', '-i', 'python']' returned non-zero exit status 1.
    ----------------------------------------
    ERROR: Failed building wheel for blake2b-py
  Failed to build blake2b-py
  ERROR: Could not build wheels for blake2b-py which use PEP 517 and cannot be installed directly
  </code></pre>
  <p>When I run the command again with --verbose I am getting:</p>
  <pre><code>error: failed to run custom build command for `pyo3 v0.8.5`
  
    Caused by:
      process didn't exit successfully: `/private/var/folders/rf/h_h1jw411_l1d366hm2pybm00000gn/T/pip-install-ewvt5uxi/blake2b-py_af0db53ab76c4fb48590a7692b7f3b09/target/release/build/pyo3-3ab2c629ff3fb44d/build-script-build` (exit code: 101)
      --- stderr
      thread 'main' panicked at 'Error: pyo3 requires a nightly or dev version of Rust.', /Users/Pancake/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.8.5/build.rs:542:9
      note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
     maturin failed
      Caused by: Failed to build a native library through cargo
      Caused by: Cargo build finished with &quot;exit code: 101&quot;: `cargo rustc --message-format json --manifest-path Cargo.toml --lib --release -- -C link-arg=-undefined -C link-arg=dynamic_lookup`
    Running `maturin pep517 build-wheel -i python`
    Error: Command '['maturin', 'pep517', 'build-wheel', '-i', 'python']' returned non-zero exit status 1.
    Building wheel for blake2b-py (PEP 517) ... error
    ERROR: Failed building wheel for blake2b-py
  Failed to build blake2b-py
  ERROR: Could not build wheels for blake2b-py which use PEP 517 and cannot be installed directly
  Exception information:
  Traceback (most recent call last):
    File &quot;/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/cli/base_command.py&quot;, line 224, in _main
      status = self.run(options, args)
    File &quot;/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/cli/req_command.py&quot;, line 180, in wrapper
      return func(self, options, args)
    File &quot;/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/commands/install.py&quot;, line 361, in run
      raise InstallationError(
  pip._internal.exceptions.InstallationError: Could not build wheels for blake2b-py which use PEP 517 and cannot be installed directly
  Removed build tracker: '/private/var/folders/rf/h_h1jw411_l1d366hm2pybm00000gn/T/pip-req-tracker-zvzjdf19'
  </code></pre>