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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 _EncodeDateField(field, value):
 """Encoder for datetime.date objects."""

    if field.repeated:
        result = [d.isoformat() for d in value]
    else:
        result = value.isoformat()
    return encoding.CodecResult(value=result, complete=True)