debug a function call. Put this in your ipython startup file.

debug.py

def dbgf(f, *args, **kwargs):
    """                                                                                                                                                                                                  
    Debug a function call.                                                                                                                                                                               
                                                                                                                                                                                                         
    """
    import pdb; pdb.set_trace()
    f(*args, **kwargs)