fix(types): explicit reexport & strict equality. <!-- Thank you for contributing to Pyodide! All improvements are welcome,
     so don't be afraid to make a PR. -->

### Description

<!-- Please explain what your PR is about:
     - reasoning for the change
     - some details of updated code
     - any noteworthy choices to be aware of
	Please refer to any related issues by #<issue_id> -->

Enabling two more strictness flags.

package:
  name: mpmath
  version: 1.2.1
source:
  sha256: 604bc21bd22d2322a177c73bdb573994ef76e62edd595d17e00aff24b0667e5c
  url: https://files.pythonhosted.org/packages/d4/cf/3965bddbb4f1a61c49aacae0e78fd1fe36b5dc36c797b31f30cf07dcbbb7/mpmath-1.2.1-py3-none-any.whl
test:
  imports:
    - mpmath

package:
  name: mpmath
  version: 1.2.1
source:
  sha256: 604bc21bd22d2322a177c73bdb573994ef76e62edd595d17e00aff24b0667e5c
  url: https://files.pythonhosted.org/packages/d4/cf/3965bddbb4f1a61c49aacae0e78fd1fe36b5dc36c797b31f30cf07dcbbb7/mpmath-1.2.1-py3-none-any.whl
test:
  imports:
    - mpmath
