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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 generate():
 """ Return the generated output. """

    global MESSAGES
    keys = MESSAGES.keys()
    # the keys are sorted in the .mo file
    keys.sort()
    offsets = []
    ids = strs = ''
    for _id in keys:
        # For each string, we need size and file offset.  Each string is NUL
        # terminated; the NUL does not count into the size.
        offsets.append((len(ids), len(_id), len(strs), len(MESSAGES[_id])))
        ids += _id + '\0'
        strs += MESSAGES[_id] + '\0'
    output = ''
    # The header is 7 32-bit unsigned integers.  We don't use hash tables, so
    # the keys start right after the index tables.
    # translated string.
    keystart = 7 * 4 + 16 * len(keys)
    # and the values start after the keys
    valuestart = keystart + len(ids)
    koffsets = []
    voffsets = []
    # The string table first has the list of keys, then the list of values.
    # Each entry has first the size of the string, then the file offset.
    for o1, l1, o2, l2 in offsets:
        koffsets += [l1, o1 + keystart]
        voffsets += [l2, o2 + valuestart]
    offsets = koffsets + voffsets
    output = struct.pack("Iiiiiii",
                         0x950412deL,       # Magic
                         0,                 # Version
                         len(keys),         # # of entries
                         7 * 4,             # start of key index
                         7 * 4 + len(keys) * 8,   # start of value index
                         0, 0)              # size and offset of hash table
    output += array.array("i", offsets).tostring()
    output += ids
    output += strs
    return output