class_docstr: Calculates the number of 'False' values since the last `True` value.
  Description:
      From a series of Booleans, find the last record with a `True` value.
      Return the count of 'False' values between that record and the end of
      the series. Return nan if no values are `True`. Any nan values in the
      input are ignored. A 'True' value in the last row will result in a
      count of 0.  Inputs are converted too booleans before calculating
      the result.
  Examples:
      >>> num_false_since_last_true = NumFalseSinceLastTrue()
      >>> num_false_since_last_true([True, False, True, False, False])
      2
code: def get_function(self):
      def num_false_since_last_true(x):
          if x.empty:
              return np.nan
          x = x.dropna().astype(bool)
          true_indices = x[x]
          if true_indices.empty:
              return np.nan
          last_true_index = true_indices.index[-1]
          x_slice = x.loc[last_true_index:]
          return np.invert(x_slice).sum()
  
      return num_false_since_last_true
  
imports: import numpy
  from woodwork.column_schema import ColumnSchema
  from woodwork.logical_types import Boolean, IntegerNullable
  from featuretools.primitives.base import AggregationPrimitive
label_desc: Use image node_id 1 for calling the NumFalseSinceLastTrue obj's underlying member method code with example usage: obj.get_function() and returns: num_false_since_last_true, np, np, np