Gate hierarchy for qiskit

gates.py

class Gate:
  def apply(self, circuit: BaseQuantumCircuit) -> None
  def qasm(self) -> String

class InvertibleGate(Gate):
  def inverse(self) -> InvertibleGate
  
class HGate(InvertibleGate):
   implementation...
 
class CNotGate(InvertibleGate):
  etc...

class HGateMixin(BaseQuantumCircuit):
  def h(self, params):
    gate = HGate(...) # Construct hgate
    gate.apply(self) # Apply hgate. The types add up since self inherits from BaseQuantumCircuit
  
class CNotMixin:
  etc...
  
  
class StandardGateMixins(HGateMixin, CNotMixin, ...(all standard gate-mixins)):
  """Repackage all standard mixins into one for exporting."""
  
  
class QuantumCircuit(StandardGateMixins):
  """Would want to inherit from BaseQuantumCircuit and StandardGateMixins for clarity but cannot,
  because of multiple inheritance conflict.
  Still, QuantumCircuit inherits from BaseQuantumCircuit through the mixins."""
  implementation...