Python bindings: Add proclaim_f, a cry_f version of proclaim

Addresses the request in
#1676 (comment)

saw-remote-api/python/CHANGELOG.md

@@ -26,6 +26,9 @@
   function with LLVM or JVM verification will raise an error.
 * The `proclaim` function (which is the Python counterpart to to
   `{llvm,jvm,mir}_assert` in SAWScript) is no longer deprecated.
+* Add a `proclaim_f` function. This behaves like the `proclaim` function, except
+  that it takes a `cry_f`-style format string as an argument. That is,
+  `proclaim_f(...)` is equivalent to `proclaim(cry_f(...))`.
 
 ## 1.0.1 -- YYYY-MM-DD
 

saw-remote-api/python/saw_client/crucible.py

@@ -536,6 +536,12 @@ def proclaim(self, proposition : Union[str, CryptolTerm, cryptoltypes.CryptolJSO
         else:
             raise Exception("wrong state")
 
+    def proclaim_f(self, s : str) -> None:
+        """Proclaims an assertion using a ``cry_f``-style format string, i.e.
+        ``proclaim_f(...)`` is equivalent to ``proclaim(cry_f(...))``"""
+        expression = to_cryptol_str_customf(s, frames=1, filename="<proclaim_f>")
+        return self.proclaim(expression)
+
     def precondition(self, proposition : Union[str, CryptolTerm, cryptoltypes.CryptolJSON]) -> None:
         """Establishes ``proposition`` as a precondition for the function ```Contract```
         being specified.