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diff --git a/challenge-285/ppentchev/python/src/perl_weekly_285/ch-1.py b/challenge-285/ppentchev/python/src/perl_weekly_285/ch-1.py
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+# SPDX-FileCopyrightText: Peter Pentchev <roam@ringlet.net>
+# SPDX-License-Identifier: BSD-2-Clause
+"""Solve the first task in Perl weekly challenge 285, "No Connection"."""
+
+from __future__ import annotations
+
+import dataclasses
+import typing
+
+from . import defs
+
+
+if typing.TYPE_CHECKING:
+    from typing import Final
+
+
+@dataclasses.dataclass
+class NoLeafError(defs.NoSolutionError):
+    """No leaf destinations at all."""
+
+    def __str__(self) -> str:
+        """Provide a human-readable error message."""
+        return "No leaf destinations could be found"
+
+
+@dataclasses.dataclass
+class MultipleLeavesError(defs.NoSolutionError):
+    """More than one leaf destination."""
+
+    multiple: list[str]
+    """The leaf destinations found."""
+
+    def __str__(self) -> str:
+        """Provide a human-readable error message."""
+        return f"Multiple leaf destinations found: {self.multiple!r}"
+
+
+def solve_no_connection(routes: list[tuple[str, str]]) -> str:
+    """Solve the first task, "No Connection."""
+    loc_from: Final = {item[0] for item in routes}
+    loc_to: Final = {item[1] for item in routes}
+    match sorted(loc_to - loc_from):
+        case []:
+            raise NoLeafError
+
+        case [single]:
+            return single
+
+        case multiple:
+            raise MultipleLeavesError(multiple)