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+## enroll/sopsutil.py
+
+### SopsError (exception class)
+
+#### Purpose: a specific exception type for SOPS-related failures.
+
+#### Behavior:
+
+- Subclasses RuntimeError but adds no extra fields/methods.
+- Used so the CLI can catch it and print a clean error: ... message.
+
+#### Raised when:
+- sops is not present on PATH but required
+- encryption/decryption subprocess fails
+- missing/empty GPG fingerprint list
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