self: rec {
  mistune_0_8 = self.callPackage ./common.nix {
    version = "0.8.4";
    sha256 = "59a3429db53c50b5c6bcc8a07f8848cb00d7dc8bdb431a4ab41920d201d4756e";
  };
  mistune_2_0 = self.callPackage ./common.nix {
    version = "2.0.0a4";
    sha256 = "0i6cblmjl58kdmaa21xm0l1ls0kvjpfy45sf73fw3ws6305f628k";
  };
  mistune = mistune_0_8;
}