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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 _get_inherited_field_types(class_to_field_type_overrides, schema_graph):
 """Return a dictionary describing the field type overrides in subclasses."""

    inherited_field_type_overrides = dict()
    for superclass_name, field_type_overrides in class_to_field_type_overrides.items():
        for subclass_name in schema_graph.get_subclass_set(superclass_name):
            inherited_field_type_overrides.setdefault(subclass_name, dict())
            inherited_field_type_overrides[subclass_name].update(field_type_overrides)
    return inherited_field_type_overrides