Fix flake8.

src/lbmpy/__init__.py

@@ -38,6 +38,7 @@ __all__ = [
     "Method",
     "ForceModel",
     "CollisionSpace",
+    "SubgridScaleModel",
     "LatticeBoltzmannStep",
     "pdf_initialization_assignments",
     "macroscopic_values_getter",

src/lbmpy/creationfunctions.py

@@ -735,7 +735,7 @@ def create_lb_collision_rule(lb_method=None, lbm_config=None, lbm_optimisation=N
                                        eddy_viscosity_field=lbm_config.eddy_viscosity_field)
 
     if 'split_groups' in collision_rule.simplification_hints:
-            collision_rule.simplification_hints['split_groups'][0].append(sp.Symbol("sgs_omega"))
+        collision_rule.simplification_hints['split_groups'][0].append(sp.Symbol("sgs_omega"))
 
     elif lbm_config.cassons:
         collision_rule = add_cassons_model(collision_rule, parameter=lbm_config.cassons,

src/lbmpy/enums.py

@@ -222,6 +222,7 @@ class ForceModel(Enum):
     See :class:`lbmpy.forcemodels.CentralMoment`
     """
 
+
 class SubgridScaleModel(Enum):
     """
     The SubgridScaleModel enumeration defines which subgrid-scale model (SGS) is used to perform

src/lbmpy/turbulence_models.py

@@ -123,7 +123,7 @@ def add_qr_model(collision_rule, qr_constant, omega_output_field=None, eddy_visc
         base_viscosity = sp.Symbol("qr_base_viscosity")
         nu_e_assignments = [
             Assignment(base_viscosity, sp.Float(6) * nu_0 + sp.Float(1)),
-            Assignment(nu_e, (-base_viscosity + sp.sqrt(base_viscosity ** 2 + sp.Float(72) * c_pi_s / rho)) \
+            Assignment(nu_e, (-base_viscosity + sp.sqrt(base_viscosity ** 2 + sp.Float(72) * c_pi_s / rho))
                        / sp.Float(12))
         ]
     else:
@@ -133,8 +133,8 @@ def add_qr_model(collision_rule, qr_constant, omega_output_field=None, eddy_visc
 
     eqs = [Assignment(nu_0, lattice_viscosity_from_relaxation_rate(omega_s)),
            *[Assignment(matrix_entries[i], pi[i]) for i in range(stencil.D ** 2)],
-           Assignment(r_prime, sp.Float(-1)**(stencil.D+1) * matrix_entries.det()),
-           Assignment(q_prime, sp.Rational(1, 2) * (matrix_entries*matrix_entries).trace()),
+           Assignment(r_prime, sp.Float(-1) ** (stencil.D + 1) * matrix_entries.det()),
+           Assignment(q_prime, sp.Rational(1, 2) * (matrix_entries * matrix_entries).trace()),
            Assignment(c_pi_s, c_pi),
            *nu_e_assignments,
            Assignment(adapted_omega, relaxation_rate_from_lattice_viscosity(nu_0 + nu_e))]