How to get the condition number of the PETScMatrix

Hello everyone! I’m new one to use the library dolfin to solve the electromagnetic problems. I assembled the matrix of the left variational formula, and want to get the condition number of the assembled PETSCMatrix, but I can’t find the corresponding function. Can anyone tell which function in library dolfin can help me get the condition number?

See for instance: How to compute the condition number efficiently? - #2 by dokken