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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 _join_list(lst, oxford=False):
 """Join a list of words in a gramatically correct way."""

    if len(lst) > 2:
        s = ', '.join(lst[:-1])
        if oxford:
            s += ','
        s += ' and ' + lst[-1]
    elif len(lst) == 2:
        s = lst[0] + ' and ' + lst[1]
    elif len(lst) == 1:
        s = lst[0]
    else:
        s = ''
    return s