Who wrote the book of Ezra?

Jewish tradition is strong that Ezra was the actual author of the Book of Ezra. Ezra and Nehemiah were joined as one book among the writings in Hebrew and Greek Old Testament giving events in restored Jerusalem after the exile. Each book contains material found in the other (for example, the list in Ezra 2 is also in Neh. 7). Jewish tradition says Ezra or Nehemiah was the author of Nehemiah. Because of the close connection between Chronicles and Ezra-Nehemiah, one person might have written or compiled all three books.