Finds package name of file

        :param root_package: root package
        :return: package name

def _find_package(self, root_package):
        """Finds package name of file

        :param root_package: root package
        :return: package name
        """

        package = self.path.replace(root_package, "")
        if package.endswith(".py"):
            package = package[:-3]

        package = package.replace(os.path.sep, MODULE_SEP)
        root_package = get_folder_name(root_package)

        package = root_package + package  # add root
        return package