def METHOD_NAME(self, tag, attrs):
    """
    While parsing the html:
    1. determine whether a div tag encountered by the parser has the unique
    class attributes assigned to the div that contains provenance data. If
    this div is encountered, the provenance_div flag is set to True.
    2. if a anchor tag is encountered within this div tag, set the
    provenance_a flag to True.
    """
    if tag == "div":
        if ("class", "views-field views-field-field-provenance-tax") in attrs:
            self.provenance_div = True
    if tag == "a":
        if self.provenance_div:
            self.provenance_a = True