def __init__(self, package, version):
        """Construct a new requirement.

        :param package: the package name.
        :param version: a semver compatible version specification.
        """
        self.package = package
        self.version = version
        if self.version and not re.match(r"[<=>~]", version[:2]):
            self.version = "=={}".format(self.version)
def remove_attributes(self, model):
        """
        Removes the x and y attributes which were added by the forward handles
        Recursively searches for non-container layers
        """
        for child in model.children():
            if 'nn.modules.container' in str(type(child)):
                self.remove_attributes(child)
            else:
                try:
                    del child.x
                except AttributeError:
                    pass
                try:
                    del child.y
                except AttributeError:
                    pass