prototype_to_improve_molecule_utils_verbose_flag

import re


_VERB_OPT_RE = re.compile(r"v+")


def verbose_flag(options, verb_re=_VERB_OPT_RE):
    """
    Return computed verbosity flag.

    :param options: A mapping object holding CLI options
    :return: A list of strings give verbose option

    >>> verbose_flag({})
    []
    >>> verbose_flag(dict(become=True))
    []
    >>> verbose_flag(dict(v=True))
    ['-v']
    >>> verbose_flag(dict(v=False))
    []
    >>> verbose_flag(dict(verbose=True))
    ['-v']
    >>> verbose_flag(dict(vvv=True))
    ['-vvv']
    >>> verbose_flag(dict(vvvvvvvvv=True))
    ['-vvvv']
    """
    if not options:
        return []

    if options.get("verbose", False):
        return ["-v"]

    # verbs: eg. [('vvv', True)]
    verbs = [(k, v) for k, v in options.items() if verb_re.match(k)]
    if verbs and verbs[0][-1]:  # [('vvv', True)] -> True
        return ["-{}".format(verbs[0][0][:4])]

    return []