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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 _encode_mapping(name, value, check_keys, opts):
 """Encode a mapping type."""

    data = b"".join([_element_to_bson(key, val, check_keys, opts)
                     for key, val in iteritems(value)])
    return b"\x03" + name + _PACK_INT(len(data) + 5) + data + b"\x00"