code: def check_version(version, fallback="master"):
      
      parse = Version(version)
      if parse.local is not None:
          return fallback
      return version
docs: Check that a version string is PEP440 compliant and there are no unreleased changes.
  
      For example, ``version = "0.1"`` will be returned as is but
      ``version = "0.1+10.8dl8dh9"`` will return the fallback. This is the convention used
      by `versioneer <https://github.com/warner/python-versioneer>`__ to mark that this
      version is 10 commits ahead of the last release.
  
      Parameters
      ----------
      version : str
          A version string.
      fallback : str
          What to return if the version string has unreleased changes.
  
      Returns
      -------
      version : str
          If *version* is PEP440 compliant and there are unreleased changes, then return
          *version*. Otherwise, return *fallback*.
  
      Raises
      ------
      InvalidVersion
          If *version* is not PEP440 compliant.
  
      Examples
      --------
  
      >>> check_version("0.1")
      '0.1'
      >>> check_version("0.1a10")
      '0.1a10'
      >>> check_version("0.1+111.9hdg36")
      'master'
      >>> check_version("0.1+111.9hdg36", fallback="dev")
      'dev'