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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 _all(field, value, document):
 """ Returns True if the value of document field contains all the values specified by ``value``. If supplied value is not an iterable, a MalformedQueryException is raised. If the value of the document field is not an iterable, False is returned """

    try:
        a = set(value)
    except TypeError:
        raise MalformedQueryException("'$all' must accept an iterable")

    try:
        b = set(document.get(field, []))
    except TypeError:
        return False
    else:
        return a.intersection(b) == a