import re


def rm_quotation_marks(sent):
    """ Remove single quotes used as quotation marks (e.g. some 'phrase in quotes')
    Remove double quotes used as quotation marks (e.g. some "phrase in quotes" or
    ``phrase in quotes'')
    """
    sent = re.sub(r"\s'([\w\s]+[\w])'\s", r' \1 ', sent)
    return re.sub(r'["“”‘’]', r' ', sent)