class_docstr: Determines the number of peaks in a list of numbers.
  
  Description:
      Given a list of numbers, count the number of local
      maxima. Uses the find_peaks function from scipy.signal.
  
  Examples:
      >>> num_peaks = NumPeaks()
      >>> num_peaks([-5, 0, 10, 0, 10, -5, -4, -5, 10, 0])
      4
code: def get_function(self):
      def num_peaks(x):
          if x.dtype == "Int64":
              x = x.astype("float64")
          peaks = find_peaks(x)[0]
          return len(peaks[~pd.isna(peaks)])
  
      return num_peaks
  
imports: import pandas
  from scipy.signal import find_peaks
  from woodwork.column_schema import ColumnSchema
  from woodwork.logical_types import Integer
  from featuretools.primitives.base import AggregationPrimitive
label_desc: Use image node_id 1 for calling the NumPeaks obj's underlying member method code with example usage: obj.get_function() and returns: num_peaks, len