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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 _field_to_json(field, row_value):
 """Convert a field into JSON-serializable values. Args: field ( \ :class:`~google.cloud.bigquery.schema.SchemaField`, \ ):
 The SchemaField to use for type conversion and field name. row_value (Union[ \ Sequence[list], \ any, \ ]):
 Row data to be inserted. If the SchemaField's mode is REPEATED, assume this is a list. If not, the type is inferred from the SchemaField's field_type. Returns: any: A JSON-serializable object. """

    if row_value is None:
        return None

    if field.mode == "REPEATED":
        return _repeated_field_to_json(field, row_value)

    if field.field_type == "RECORD":
        return _record_field_to_json(field.fields, row_value)

    return _scalar_field_to_json(field, row_value)