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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def from_scf_input(cls, workdir, scf_input, ph_ngqpt, with_becs=True, manager=None, allocate=True):
 """ Create a `PhononFlow` for phonon calculations from an `AbinitInput` defining a ground-state run. Args: workdir: Working directory of the flow. scf_input: :class:`AbinitInput` object with the parameters for the GS-SCF run. ph_ngqpt: q-mesh for phonons. Must be a sub-mesh of the k-mesh used for electrons. e.g if ngkpt = (8, 8, 8). ph_ngqpt = (4, 4, 4) is a valid choice whereas ph_ngqpt = (3, 3, 3) is not! with_becs: True if Born effective charges are wanted. manager: :class:`TaskManager` object. Read from `manager.yml` if None. allocate: True if the flow should be allocated before returning. Return: :class:`PhononFlow` object. """

        flow = cls(workdir, manager=manager)

        # Register the SCF task
        flow.register_scf_task(scf_input)
        scf_task = flow[0][0]

        # Make sure k-mesh and q-mesh are compatible.
        scf_ngkpt, ph_ngqpt = np.array(scf_input["ngkpt"]), np.array(ph_ngqpt)

        if any(scf_ngkpt % ph_ngqpt != 0):
            raise ValueError("ph_ngqpt %s should be a sub-mesh of scf_ngkpt %s" % (ph_ngqpt, scf_ngkpt))

        # Get the q-points in the IBZ from Abinit
        qpoints = scf_input.abiget_ibz(ngkpt=ph_ngqpt, shiftk=(0, 0, 0), kptopt=1).points

        # Create a PhononWork for each q-point. Add DDK and E-field if q == Gamma and with_becs.
        for qpt in qpoints:
            if np.allclose(qpt, 0) and with_becs:
                ph_work = BecWork.from_scf_task(scf_task)
            else:
                ph_work = PhononWork.from_scf_task(scf_task, qpoints=qpt)

            flow.register_work(ph_work)

        if allocate: flow.allocate()

        return flow