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| |
| <html> |
| <h2>CoGroupByKey</h2> |
| <p> |
| CoGroupByKey performs a relational join of two or more key/value PCollections that have the same |
| key type. |
| </p> |
| <p> |
| <b>Kata:</b> Implement a |
| <a href="https://beam.apache.org/releases/pydoc/current/apache_beam.transforms.util.html#apache_beam.transforms.util.CoGroupByKey"> |
| CoGroupByKey</a> transform that join words by its first alphabetical letter, and then produces |
| the string representation of the WordsAlphabet model. |
| </p> |
| <br> |
| <div class="hint"> |
| Refer to |
| <a href="https://beam.apache.org/releases/pydoc/current/apache_beam.transforms.util.html#apache_beam.transforms.util.CoGroupByKey"> |
| CoGroupByKey</a>to solve this problem. |
| </div> |
| <div class="hint"> |
| Refer to the Beam Programming Guide |
| <a href="https://beam.apache.org/documentation/programming-guide/#cogroupbykey"> |
| "CoGroupByKey"</a> section for more information. |
| </div> |
| </html> |
