add a method IDMapping.identity for convenience

1 files changed, 5 insertions, 0 deletions

diff --git a/linuxnamespaces/__init__.py b/linuxnamespaces/__init__.py
index 8c1def3..a2c7985 100644
--- a/linuxnamespaces/__init__.py
+++ b/linuxnamespaces/__init__.py
@@ -59,6 +59,11 @@ class IDMapping:
         if self.innerstart + self.count >= 1 << 64:
             raise ValueError("innerstart + count exceed 64bits")
 
+    @classmethod
+    def identity(cls, idn: int, count: int = 1) -> typing.Self:
+        """Construct an identity mapping for the given identifier."""
+        return cls(idn, idn, count)
+
 
 class IDAllocation:
     """This represents a subset of IDs (user or group). It can be used to