def __init__(self, groups=None):
        super(GroupedRequirements, self).__init__(NamedRequirements)
        self.groups = groups or self.default_groups
        self.filename = None
        self.create_default_groups()
def projectdir(self):
        """Absolute location of project directory: WM_PROJECT_DIR/"""
        return self.prefix  # <- install directly under prefix