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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def findFirstHref(link_attrs_list, target_rel):
 """Return the value of the href attribute for the first link tag in the list that has target_rel as a relationship."""

    # XXX: TESTME
    matches = findLinksRel(link_attrs_list, target_rel)
    if not matches:
        return None
    first = matches[0]
    return first.get('href')