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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 ion_equals(a, b, timestamps_instants_only=False):
 """Tests two objects for equivalence under the Ion data model. There are three important cases: * When neither operand specifies its `ion_type` or `annotations`, this method will only return True when the values of both operands are equivalent under the Ion data model. * When only one of the operands specifies its `ion_type` and `annotations`, this method will only return True when that operand has no annotations and has a value equivalent to the other operand under the Ion data model. * When both operands specify `ion_type` and `annotations`, this method will only return True when the ion_type and annotations of both are the same and their values are equivalent under the Ion data model. Note that the order of the operands does not matter. Args: a (object):
 The first operand. b (object):
 The second operand. timestamps_instants_only (Optional[bool]):
 False if timestamp objects (datetime and its subclasses) should be compared according to the Ion data model (where the instant, precision, and offset must be equal); True if these objects should be considered equivalent if they simply represent the same instant. """

    if timestamps_instants_only:
        return _ion_equals_timestamps_instants(a, b)
    return _ion_equals_timestamps_data_model(a, b)