chore: Remove guppy test dependency (#516)

Removes the dependency on the guppy package, to avoid dependency cycles.
The lowering tests here are being moved to the guppy project instead.

Author: aborgna-q

poetry.lock

@@ -41,7 +41,6 @@ mypy = "^1.11.0"
 hypothesis = "^6.108.5"
 graphviz = "^0.20"
 pre-commit = "^3.8.0"
-guppylang = {git = "https://github.com/CQCL/guppylang", branch = "doug/hugr-0.10.0"}
 
 [build-system]
 requires = ["maturin~=1.7"]

pyproject.toml

@@ -1,9 +1,14 @@
 """Some utility functions for the example notebooks."""
 
+from typing import TYPE_CHECKING, Any
 from tket2.passes import lower_to_pytket
 from tket2.circuit import Tk2Circuit
 
-from guppylang.definition.function import RawFunctionDef
+if TYPE_CHECKING:
+    try:
+        from guppylang.definition.function import RawFunctionDef  # type: ignore[import-untyped, import-not-found, unused-ignore]  # noqa: F401
+    except ImportError:
+        RawFunctionDef = Any
 
 
 # We need to define this helper function for now. It will be included in guppy in the future.