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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def query_file(self, path, fetchall=False, **params):
 """Like Connection.query, but takes a filename to load a query from."""


        # If path doesn't exists
        if not os.path.exists(path):
            raise IOError("File '{}' not found!".format(path))

        # If it's a directory
        if os.path.isdir(path):
            raise IOError("'{}' is a directory!".format(path))

        # Read the given .sql file into memory.
        with open(path) as f:
            query = f.read()

        # Defer processing to self.query method.
        return self.query(query=query, fetchall=fetchall, **params)