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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 get_family(families):
 """Return the first installed font family in family list"""

    if not isinstance(families, list):
        families = [ families ]
    for family in families:
        if font_is_installed(family):
            return family
    else:
        print("Warning: None of the following fonts is installed: %r" % families)  # spyder: test-skip
        return QFont().family()