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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 encode(self, tf_graph_predictions):
 """Encodes the graph json prediction into csv. Args: tf_graph_predictions: python dict. Returns: csv string. """

    row = []
    for col in self._header:
      row.append(str(tf_graph_predictions[col]))

    return ','.join(row)