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:
| District | Incumbent | Party | First elected | Result | Candidates |
| --- | --- | --- | --- | --- | --- |
| Pennsylvania 2 | William T. Granahan | Democratic | 1948.0 | Re-elected | William T. Granahan (D) 57.0% Max Slepin (R) 43.0% |
| Pennsylvania 3 | Hardie Scott | Republican | 1946.0 | Re-elected | Hardie Scott (R) 50.3% Maurice S. Osser (D) 49.7% |
| Pennsylvania 9 | Paul B. Dague | Republican | 1946.0 | Re-elected | Paul B. Dague (R) 67.2% Philip Ragan (D) 32.8% |
| Pennsylvania 12 | Ivor D. Fenton | Republican | 1938.0 | Re-elected | Ivor D. Fenton (R) 56.8% James H. Gildea (D) 43.2% |
| Pennsylvania 19 | Leon H. Gavin | Republican | 1942.0 | Re-elected | Leon H. Gavin (R) 62.8% Fred C. Barr (D) 37.2% |
| Pennsylvania 21 | James F. Lind | Democratic | 1948.0 | Re-elected | James F. Lind (D) 52.2% Francis Worley (R) 47.8% |
Question:
What is the number of candidates for pennsylvania 21
Answer:
1.0