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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 _struct_or_lob_handler(c, ctx):
 """Handles tokens that begin with an open brace."""

    assert c == _OPEN_BRACE
    c, self = yield
    yield ctx.immediate_transition(_STRUCT_OR_LOB_TABLE[c](c, ctx))