human
Solve the following python programming problem given the following code:
def sort(self, cmp = None, key = None, reverse = False) : 
    'Sorts rows in the texttable.

    Args:
      cmp: func, non default sort algorithm to use.
      key: func, applied to each element before sorting.
      reverse: bool, reverse order of sort.
    ' 
    def _DefaultKey(value) : 
        'Default key func is to create a list of all fields.' 
        result = [] 
        for key in self.header : 
            try : 
                result.append (float (value [key])) 
except ValueError : 
                result.append (value [key]) 
return result 
key = (key or _DefaultKey) 
    new_table = self._table [1 :] 
    new_table.sort (cmp, key, reverse) 
    self._table = [self.header] 
    self._table.extend (_DefaultKey) 
    for (index, row) in enumerate (self._table) : 
        row.row = index 

    
    

    Fix the buggy line: self._table.extend (_DefaultKey)
assistant
#Here is Python program to fix the buggy line: self.

self._table.extend (new_table)