Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Date | Visitor | Score | Home | Decision | Attendance | Record |
| --- | --- | --- | --- | --- | --- | --- |
| January 4 | Boston | 3 – 2 | Philadelphia | Parent | 10097.0 | 17–13–5 |
| January 6 | Philadelphia | 2 – 2 | Pittsburgh | Favell | 7351.0 | 17–13–6 |
| January 7 | Pittsburgh | 1 – 3 | Philadelphia | Favell | 7935.0 | 18–13–6 |
| January 10 | Philadelphia | 4 – 6 | Minnesota | Favell | 9768.0 | 18–14–6 |
| January 11 | Montreal | 4 – 2 | Philadelphia | Parent | 14126.0 | 18–15–6 |
| January 14 | Philadelphia | 6 – 3 | California | Parent | 2878.0 | 19–15–6 |
| January 18 | Philadelphia | 4 – 2 | Minnesota | Favell | 9098.0 | 20–15–6 |
| January 20 | Philadelphia | 2 – 4 | Boston | Parent | 13527.0 | 20–16–6 |
| January 21 | St. Louis | 2 – 2 | Philadelphia | Parent | 10834.0 | 20–16–7 |
| January 24 | Philadelphia | 2 – 1 | Toronto | Favell | 15834.0 | 21–16–7 |
| January 25 | Minnesota | 3 – 0 | Philadelphia | Parent | 9334.0 | 21–17–7 |
| January 27 | Philadelphia | 2 – 3 | Detroit | Parent | 12820.0 | 21–18–7 |
| January 28 | Los Angeles | 2 – 0 | Philadelphia | Favell | 13577.0 | 21–19–7 |
Question:
Decision of parent, and a Home of philadelphia, and a Record of 20–16–7 is on what date?
Answer:
January 21