Bug in subdag with external inputs

[elijahbenizzy]

Short description explaining the high-level reason for the new issue.

Current behavior

Not sure why this happens, but this fails:

from hamilton.function_modifiers import extract_fields, subdag, config, source
from hamilton import version

def bar(baz: int) -> int:
    return baz

def foo(bar: int) -> int:
    return bar

@subdag(foo, inputs={'baz' : source("qux")}, config={})
def foo_subdag(foo: int) -> int:
    return foo

from hamilton import driver, base
from hamilton.ad_hoc_utils import create_temporary_module

mod = create_temporary_module(foo_subdag)
dr = driver.Driver({}, mod, adapter=base.SimplePythonGraphAdapter(base.DictResult()))
print(dr.execute(['foo_subdag'], inputs={'qux' : 1}))

Stack Traces

(If applicable)

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Traceback (most recent call last):
  File "/Users/elijahbenizzy/dev/dagworks/os/hamilton/./subdag_external_input.py", line 18, in <module>
    dr = driver.Driver({}, mod, adapter=base.SimplePythonGraphAdapter(base.DictResult()))
  File "/Users/elijahbenizzy/dev/dagworks/os/hamilton/hamilton/driver.py", line 126, in __init__
    raise e
  File "/Users/elijahbenizzy/dev/dagworks/os/hamilton/hamilton/driver.py", line 121, in __init__
    self.graph = graph.FunctionGraph(*modules, config=config, adapter=adapter)
  File "/Users/elijahbenizzy/dev/dagworks/os/hamilton/hamilton/graph.py", line 169, in __init__
    self.nodes = create_function_graph(*modules, config=self._config, adapter=adapter)
  File "/Users/elijahbenizzy/dev/dagworks/os/hamilton/hamilton/graph.py", line 77, in create_function_graph
    for n in fm_base.resolve_nodes(f, config):
  File "/Users/elijahbenizzy/dev/dagworks/os/hamilton/hamilton/function_modifiers/base.py", line 688, in resolve_nodes
    nodes = node_creator.generate_nodes(fn, filter_config(config, node_creator))
  File "/Users/elijahbenizzy/dev/dagworks/os/hamilton/hamilton/function_modifiers/recursive.py", line 391, in generate_nodes
    nodes += self._create_additional_static_nodes(nodes, namespace)
  File "/Users/elijahbenizzy/dev/dagworks/os/hamilton/hamilton/function_modifiers/recursive.py", line 270, in _create_additional_static_nodes
    typ=node_types[new_node_name],
KeyError: 'foo_subdag.baz'```


## Steps to replicate behavior
1. Run the script above

## Library & System Information
Newest Hamilton.


# Expected behavior
It should work

# Additional context
Add any other context about the problem here.

[elijahbenizzy]

This example wasn't making proper use of external_inputs, and is a duplicate of #188