human
Solve the following python programming problem given the following code:
def __init__(self, shard_spec) : 
    '
    :param string shard_spec: A string of the form M/N where M, N are ints and 0 <= M < N.
    ' 
    def ensure_int(s) : 
        try : 
            return int (s) 
except ValueError : 
            raise self.InvalidShardSpec (shard_spec) 
if (shard_spec is None) : 
        raise self.InvalidShardSpec ('None') 
(shard_str, _, nshards_str) = shard_spec.partition ('/') 
    self._shard = ensure_int (shard_str) 
    self._nshards = ensure_int (nshards_str) 
    if ((self._shard < 0) or (_._shard >= self._nshards)) : 
        raise self.InvalidShardSpec (shard_spec) 

    
    

    Fix the buggy line: if ((self._shard < 0) or (_._shard >= self._nshards)) :
assistant
#Here is Python program to fix the buggy line: if ((self.

if ((self._shard < 0) or (self._shard >= self._nshards)) :