Modify get_name_by_grand_child function

[Tyrica Terry Kapral]

Modify function so that matches for creator include and matches for contributor exclude the following roleTerm values: 'author', 'aut', 'composer', 'cmp', 'creator', cre', 'dubious author', 'dub', 'editor', 'edt', 'screenwriter', 'aus'.

And so that there are two ways to handle instances when there is no role subelement:

• grand_child_element_value='creator' and 'name[usage="primary"]
• grand_child_element_value='contributor' and not( 'name[usage="primary"] )

def get_name_by_grand_child(bs_object, grand_child_exp, grand_child_element_value, children='namePart' ):
    """
    This function accepts a BeautifulSoup object, find role > roleTerm="creator", "depositor", or 
    "contributor", and then if it matches, we return all namePart element values, comma separated
    """

    # matches where roleTerm = grand_child_element_value
    grand_children = bs_object.select(grand_child_exp)

    all_matches_joined = ""
    
    match = False
    for g in grand_children:

        if g.text == grand_child_element_value:
            match = True
            break
    if match:
        all_matches = bs_object.select(children)
        all_matches_joined += ", ".join([i.text for i in all_matches])
        
    # matches where there is no role, and grand_child_element_value=contributor
    if grand_child_element_value == 'contributor':
        no_roles = bs_object.select('role')
        if len(no_roles) == 0:
            all_matches = bs_object.select(children)
            all_matches_joined += ", ".join([i.text for i in all_matches])
    return all_matches_joined