function pep440VersionColor(version) {
  if (!pep440.valid(version)) {
    return 'lightgrey'
  }
  const parsedVersion = pep440.explain(version)
  if (parsedVersion.is_prerelease || parsedVersion.public.startsWith('0.')) {
    return 'orange'
  }
  return 'blue'
}
Determines the color used for a badge based on PEP440 versioning.

@param {string|number} version Version used for determining badge color
@returns {string} Badge color