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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_generic_fields():
 """Return a list of all GenericForeignKeys in all models."""

    generic_fields = []
    for model in apps.get_models():
        for field_name, field in model.__dict__.items():
            if isinstance(field, GenericForeignKey):
                generic_fields.append(field)
    return generic_fields