# Buggy code
def from_pytd(cls, vm, name, sig):
    """Construct an abstract signature from a pytd signature."""
    # TODO(kramm): templates
    pytd_annotations = [
        (p.name, p.type)
        for p in sig.params + (sig.starargs, sig.starstarargs)
        if p is not None
    ]
    pytd_annotations.append(("return", sig.return_type))

    def param_to_var(p):
        return vm.convert.constant_to_var(
            p.type, subst=datatypes.AliasingDict(), node=vm.root_cfg_node
        )

    return cls(
        name=name,
        param_names=tuple(p.name for p in sig.params if not p.kwonly),
        varargs_name=None if sig.starargs is None else sig.starargs.name,
        kwonly_params=set(p.name for p in sig.params if p.kwonly),
        kwargs_name=None if sig.starstarargs is None else sig.starstarargs.name,
        defaults={p.name: param_to_var(p) for p in sig.params if p.optional},
        annotations={
            name: vm.convert.constant_to_value(
                typ, subst=datatypes.AliasingDict(), node=vm.root_cfg_node
            )
            for name, typ in pytd_annotations
        },
        late_annotations={},
        postprocess_annotations=False,
    )


# Traceback (AttributeError)
from typing import Any
def __getattr__(name: Any) -> Any: ...
# Caught error in pytype: 'LateAnnotation' object has no attribute 'Bindings'
# Traceback (most recent call last):
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/io.py", line 131, in check_or_generate_pyi
#     input_filename=options.input, options=options, loader=loader)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/io.py", line 89, in generate_pyi
#     analyze.infer_types, input_filename, options, loader)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/io.py", line 62, in _call
#     deep=deep)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/analyze.py", line 668, in infer_types
#     tracer.exitpoint = tracer.analyze(loc, defs, maximum_depth)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/analyze.py", line 407, in analyze
#     return self.analyze_toplevel(node, defs)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/analyze.py", line 370, in analyze_toplevel
#     new_node = self.analyze_class(node, value)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/analyze.py", line 352, in analyze_class
#     node = self.analyze_method_var(node, name, b)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/analyze.py", line 202, in analyze_method_var
#     node2 = self.maybe_analyze_method(node1, val)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/analyze.py", line 157, in maybe_analyze_method
#     node, _ = self.call_function_with_args(node, val, args)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/analyze.py", line 121, in call_function_with_args
#     new_node, ret = self.call_function_in_frame(node, fvar, *args)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/analyze.py", line 132, in call_function_in_frame
#     state, var, args, kwargs, starargs, starstarargs)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/vm.py", line 917, in call_function_with_state
#     starstarargs=starstarargs), fallback_to_unsolvable, allow_noreturn=True)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/vm.py", line 953, in call_function
#     new_node, one_result = func.call(node, funcv, args)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/abstract.py", line 3247, in call
#     alias_map=self.alias_map)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/abstract.py", line 3051, in call
#     node2, ret = self.vm.run_frame(frame, node)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/vm.py", line 292, in run_frame
#     state = self.run_instruction(op, state)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/vm.py", line 253, in run_instruction
#     state = bytecode_fn(state, op)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/vm.py", line 1980, in byte_LOAD_ATTR
#     state, val = self.load_attr(state, obj, name)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/vm.py", line 1224, in load_attr
#     node, result, errors = self._retrieve_attr(state.node, obj, attr)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/vm.py", line 1195, in _retrieve_attr
#     node, val.data, attr, val)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/attribute.py", line 65, in get_attribute
#     return self._get_instance_attribute(node, obj, name, valself)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/attribute.py", line 234, in _get_instance_attribute
#     return self._get_attribute(node, obj, obj.cls, name, valself)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/attribute.py", line 270, in _get_attribute
#     node, attr = self.get_attribute(node, cls, name, valself)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/attribute.py", line 58, in get_attribute
#     return self._get_class_attribute(node, obj, name, valself)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/attribute.py", line 229, in _get_class_attribute
#     return self._get_attribute(node, cls, meta, name, valself)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/attribute.py", line 284, in _get_attribute
#     attr = self._filter_var(node, attr)
#   File "/Users/name/.pyenv/versions/3.7.3/envs/venv/lib/python3.7/site-packages/pytype/attribute.py", line 426, in _filter_var
#     bindings = var.Bindings(node, strict=False)
# AttributeError: 'LateAnnotation' object has no attribute 'Bindings'

# Fixed code
def from_pytd(cls, vm, name, sig):
    """Construct an abstract signature from a pytd signature."""
    # TODO(kramm): templates
    pytd_annotations = [
        (p.name, p.type)
        for p in sig.params + (sig.starargs, sig.starstarargs)
        if p is not None
    ]
    pytd_annotations.append(("return", sig.return_type))

    def param_to_var(p):
        return vm.convert.constant_to_var(
            p.type, subst=datatypes.AliasingDict(), node=vm.root_cfg_node
        )

    return cls(
        name=name,
        param_names=tuple(p.name for p in sig.params if not p.kwonly),
        varargs_name=None if sig.starargs is None else sig.starargs.name,
        kwonly_params=set(p.name for p in sig.params if p.kwonly),
        kwargs_name=None if sig.starstarargs is None else sig.starstarargs.name,
        defaults={p.name: param_to_var(p) for p in sig.params if p.optional},
        annotations={
            name: vm.convert.constant_to_value(
                typ, subst=datatypes.AliasingDict(), node=vm.root_cfg_node
            )
            for name, typ in pytd_annotations
        },
        postprocess_annotations=False,
    )