def open(self):
        """Open a pre-existing on-disk database.

        @raise anydbm.error: If there's a problem opening the database.
        @raise ValueError: If the database is not of the right type.
        """
        if not self.filename:
            raise ValueError("Can only open on-disk databases")
        self.db = dbm.open(self.filename, "w") #raises anydbm.error
        try:
            if self.db["--Reserved--type"] != self.type:
                raise ValueError("Not a %s database" % self.type)
        except __HOLE__:
            raise ValueError("Not a recognized database")
dataset/ETHPy150Open kuri65536/python-for-android/python3-alpha/python-libs/gdata/tlslite/BaseDB.py/BaseDB.open