Improvement: generalize CausalGraph.from_adjacency_matrix (#53)

Description and Motivation
The cai_causal_graph.causal_graph.CausalGraph.from_adjacency_matrix is now a class method (rather than being a static method) which has been generalized to return an instance of the class on which it has been called (e.g. enabling returning instances of classes inheriting from cai_causal_graph.causal_graph.CausalGraph.

Additional Context
This is to simplify extending CausalGraph class and to bring from_adjancency_matrix in line with other class construction methods such as from_dict.

This change is completely backwards compatible since the API of the method is unchanged.

How Has This Been Tested?
Existing tests.

cai_causal_graph/causal_graph.py

@@ -1884,9 +1884,9 @@ def from_gml_string(gml: str) -> CausalGraph:
         g = networkx.parse_gml(gml)
         return CausalGraph.from_networkx(g)
 
-    @staticmethod
+    @classmethod
     def from_adjacency_matrix(
-        adjacency: numpy.ndarray, node_names: Optional[List[Union[NodeLike, int]]] = None
+        cls, adjacency: numpy.ndarray, node_names: Optional[List[Union[NodeLike, int]]] = None
     ) -> CausalGraph:
         """
         Construct a `cai_causal_graph.causal_graph.CausalGraph` instance from an adjacency matrix and optionally a list
@@ -1927,7 +1927,7 @@ def from_adjacency_matrix(
         nodes = [CausalGraph.coerce_to_nodelike(node) for node in node_names]  # type: ignore
 
         # Add edges. Any conversion from BasicFeature or BasicTarget is handled by the add_edge method.
-        graph = CausalGraph()
+        graph = cls()
         graph.add_nodes_from(nodes)
         for i, j in itertools.combinations(range(len(nodes)), 2):
             if adjacency[i, j] != 0 and adjacency[j, i] == 0:

changelog.md

@@ -20,6 +20,9 @@
 - Fixed a bug where `cai_causal_graph.causal_graph.CausalGraph.delete_edge` would not support passing source and destination
   as `cai_causal_graph.graph_components.Node`.
 - Added support for passing source and destination as `cai_causal_graph.graph_components.Node` to `cai_causal_graph.causal_graph.CausalGraph.remove_edge`.
+- The `cai_causal_graph.causal_graph.CausalGraph.from_adjacency_matrix` is now a class method (rather than being a static method)
+  which has been generalized to return an instance of the class on which it has been called (e.g. enabling returning instances of
+  classes inheriting from `cai_causal_graph.causal_graph.CausalGraph`.
 
 ## 0.3.14