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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 _number_negative_start_handler(c, ctx):
 """Handles numeric values that start with a negative sign. Branches to delegate co-routines according to _NEGATIVE_TABLE. """

    assert c == _MINUS
    assert len(ctx.value) == 0
    ctx.set_ion_type(IonType.INT)
    ctx.value.append(c)
    c, _ = yield
    yield ctx.immediate_transition(_NEGATIVE_TABLE[c](c, ctx))