code: def and_gate(variables, vartype=dimod.BINARY, name='AND'):
      
  
      variables = tuple(variables)
  
      if vartype is dimod.BINARY:
          configurations = frozenset([(0, 0, 0),
                                      (0, 1, 0),
                                      (1, 0, 0),
                                      (1, 1, 1)])
  
          def func(in1, in2, out): return (in1 and in2) == out
  
      else:
          # SPIN, vartype is checked by the decorator
          configurations = frozenset([(-1, -1, -1),
                                      (-1, +1, -1),
                                      (+1, -1, -1),
                                      (+1, +1, +1)])
  
          def func(in1, in2, out): return ((in1 > 0) and (in2 > 0)) == (out > 0)
  
      return Constraint(func, configurations, variables, vartype=vartype, name=name)
docs: AND gate.
  
      Args:
          variables (list): Variable labels for the and gate as `[in1, in2, out]`,
              where `in1, in2` are inputs and `out` the gate's output.
          vartype (Vartype, optional, default='BINARY'): Variable type. Accepted
              input values:
  
              * Vartype.SPIN, 'SPIN', {-1, 1}
              * Vartype.BINARY, 'BINARY', {0, 1}
          name (str, optional, default='AND'): Name for the constraint.
  
      Returns:
          Constraint(:obj:`.Constraint`): Constraint that is satisfied when its variables are
          assigned values that match the valid states of an AND gate.
  
      Examples:
          >>> import dwavebinarycsp
          >>> import dwavebinarycsp.factories.constraint.gates as gates
          >>> csp = dwavebinarycsp.ConstraintSatisfactionProblem(dwavebinarycsp.BINARY)
          >>> csp.add_constraint(gates.and_gate(['a', 'b', 'c'], name='AND1'))
          >>> csp.check({'a': 1, 'b': 0, 'c': 0})
          True