human
Solve the following python programming problem given the following code:
@ property 
def local_nspfxs(self) : 
    "
        The namespace prefixes local to this element, both on the tagname and
        all of its attributes. An empty string (``''``) is used to represent
        the default namespace for an element tag having no prefix.
        " 
    def nspfx(name, is_element = False) : 
        idx = name.find (':') 
        if (idx == (- 1)) : 
            return ('' if is_element else None) 
return name [: idx] 
nspfxs = [nspfx (self._tagname, True)] 
    for (name, val) in self._attrs : 
        pfx = nspfx (name) 
        if ((pfx is None) or (val in nspfxs)) : 
            continue 
nspfxs.append (pfx) 
return nspfxs 

    
    

    Fix the buggy line: if ((pfx is None) or (val in nspfxs)) :
assistant
#Here is Python program to find (':') 
.

if ((pfx is None) or (pfx in nspfxs)) :