'C{dirdbm[k]}
Get the contents of a file in this directory as a string.
@type k: bytes
@param k: key to lookup
@return: The value associated with C{k}
@raise KeyError: Raised when there is no such key'

def __getitem__(self, k):

    if (not (type(k) == bytes)):
        raise TypeError('DirDBM    key    must    be    bytes')
    path = self._dnamePath.child(self._encode(k))
    try:
        return self._readFile(path)
    except EnvironmentError:
        raise KeyError(k)
