Use legacycrypt where crypt isn't available

Since Python 3.13 has removed the crypt module, add legacycrypt to the
optional requirements, attempting to import it if the crypt module
isn't found.

Fixes #594

netutils/password.py

@@ -1,7 +1,5 @@
 """Functions for working with Passwords."""
 
-# TODO: Swap out crypt prior to py3.13
-import crypt  # pylint: disable=deprecated-module
 import random
 import secrets
 import string
@@ -247,6 +245,13 @@ def encrypt_cisco_type5(unencrypted_password: str, salt: t.Optional[str] = None,
         '$1$MHkb$v2MFmDkQX66TTxLkFF50K/'
         >>>
     """
+    try:
+        import crypt  # pylint: disable=deprecated-module
+    except ModuleNotFoundError:
+        try:
+            import legacycrypt as crypt
+        except ModuleNotFoundError:
+            raise ValueError("Crypt module not available")
     if not salt:
         salt = "".join(secrets.choice(ALPHABET) for _ in range(salt_len))
     elif not set(salt) <= set(ALPHABET):

pyproject.toml

@@ -31,7 +31,7 @@ napalm = {version = "^4.0.0", optional = true}
 jsonschema = {version = "^4.17.3", optional = true}
 
 [tool.poetry.extras]
-optionals = ["jsonschema", "napalm"]
+optionals = ["jsonschema", "napalm", "legacycrypt"]
 
 [tool.poetry.group.dev.dependencies]
 bandit = "*"