Return the distribution name with version.

    If for_filename is true, return a filename-escaped form.

def _get_name_and_version(name, version, for_filename=False):
    """Return the distribution name with version.

    If for_filename is true, return a filename-escaped form."""
    if for_filename:
        # For both name and version any runs of non-alphanumeric or '.'
        # characters are replaced with a single '-'.  Additionally any
        # spaces in the version string become '.'
        name = _FILESAFE.sub('-', name)
        version = _FILESAFE.sub('-', version.replace(' ', '.'))
    return '%s-%s' % (name, version)