  DIRECTOR │ Listening on /tmp/stepup-########/director (StepUp 2.0.4)
   STARTUP │ (Re)initialized boot script
  DIRECTOR │ Launched worker 0
     PHASE │ run
     START │ ./plan.py
      FAIL │ ./plan.py
────────────────────────────────── Step info ───────────────────────────────────
Command               ./plan.py
Return code           1
──────────────────────────────── Standard error ────────────────────────────────
Traceback (most recent call last):
  File "docs/advanced_topics/cyclic_dependencies/./plan.py", line 5, in <module>
    copy("b.txt", "a.txt")
    ~~~~^^^^^^^^^^^^^^^^^^
  File "stepup/core/api.py", line 548, in copy
    return step("cp -aT ${inp} ${out}", inp=path_src, out=path_dst, optional=optional, block=block)
  File "stepup/core/api.py", line 330, in step
    RPC_CLIENT.call.step(
    ~~~~~~~~~~~~~~~~~~~~^
        _get_step_key(),
        ^^^^^^^^^^^^^^^^
    ...<8 lines>...
        block,
        ^^^^^^
    )
    ^
  File "stepup/core/rpc.py", line 444, in __call__
    _handle_error(body, name, args, kwargs)
    ~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "stepup/core/rpc.py", line 69, in _handle_error
    raise RPCError(f"An exception was raised in the server during the call {fmt_call}: \n\n{body}")
stepup.core.exceptions.RPCError: An exception was raised in the server during the call step('step:./plan.py', 'cp -aT b.txt a.txt', [Path('b.txt')], [], [Path('a.txt')], [], Path('./'), False, None, False):
Traceback (most recent call last):
  File "stepup/core/rpc.py", line 192, in _handle_request
    result = await result
             ^^^^^^^^^^^^
  File "stepup/core/director.py", line 399, in step
    self.workflow.define_step(
    ~~~~~~~~~~~~~~~~~~~~~~~~~^
        creator,
        ^^^^^^^^
    ...<8 lines>...
        block=block,
        ^^^^^^^^^^^^
    )
    ^
  File "stepup/core/workflow.py", line 699, in define_step
    file.add_supplier(step)
    ~~~~~~~~~~~~~~~~~^^^^^^
  File "stepup/core/file.py", line 135, in add_supplier
    idep = super().add_supplier(supplier)
  File "stepup/core/cascade.py", line 374, in add_supplier
    raise CyclicError("New relation introduces a cyclic dependency")
stepup.core.exceptions.CyclicError: New relation introduces a cyclic dependency
────────────────────────────────────────────────────────────────────────────────
   WARNING │ 1 step(s) failed.
   WARNING │ 1 step(s) remained pending due to incomplete requirements
─────────────────────────────── Orphaned inputs ────────────────────────────────
             AWAITED  a.txt
───────────────────────────────── PENDING Step ─────────────────────────────────
Command               cp -aT a.txt b.txt
Working directory     ./
Inputs        STATIC  ./
             AWAITED  (a.txt)
Outputs      AWAITED  b.txt
────────────────────────────────────────────────────────────────────────────────
   WARNING │ Skipping cleanup due to incomplete build.
   WARNING │ Check logs: .stepup/fail.log .stepup/warning.log
  DIRECTOR │ Stopping workers.
  DIRECTOR │ See you!
