def file_is_present(self, file_path):
        """
        check if file 'file_path' is present, raises IOError if file_path
        is not a file

        :param file_path: str, path to the file
        :return: True if file exists, False if file does not exist
        """
        p = self.p(file_path)
        if not os.path.exists(p):
            return False
        if not os.path.isfile(p):
            raise IOError("%s is not a file" % file_path)
        return True
check if file 'file_path' is present, raises IOError if file_path
        is not a file

        :param file_path: str, path to the file
        :return: True if file exists, False if file does not exist