old_contents: from __future__ import (absolute_import, division, print_function,
                          unicode_literals)
  from .scale import scale
  from copy import deepcopy
  from matplotlib.pyplot import FuncFormatter
  
  dollar   = lambda x,pos: '$%1.2f' % x
  currency = dollar
  comma    = lambda x,pos: '{:0,d}'.format(int(x))
  millions = lambda x, pos: '$%1.1fM' % (x*1e-6)
  
  LABEL_FORMATS = {
      'comma': comma,
      'dollar': dollar,
      'currency': currency,
      'millions': millions
  }
  
  class scale_y_continuous(scale):
      VALID_SCALES = ['name', 'labels', 'limits', 'breaks', 'trans']
      def __radd__(self, gg):
          gg = deepcopy(gg)
          if self.name:
              gg.ylab = self.name.title()
          if self.labels and self.labels in LABEL_FORMATS:
              format_func = LABEL_FORMATS[self.labels]
              gg.ytick_formatter = FuncFormatter(format_func)
          if self.limits:
              gg.ylimits = self.limits
          if self.breaks:
              gg.ybreaks = self.breaks
          return gg
  
  
new_contents: from __future__ import (absolute_import, division, print_function,
                          unicode_literals)
  from .scale import scale
  from copy import deepcopy
  from matplotlib.pyplot import FuncFormatter
  
  dollar   = lambda x,pos: '$%1.2f' % x
  currency = dollar
  comma    = lambda x,pos: '{:0,d}'.format(int(x))
  millions = lambda x, pos: '$%1.1fM' % (x*1e-6)
  
  LABEL_FORMATS = {
      'comma': comma,
      'dollar': dollar,
      'currency': currency,
      'millions': millions
  }
  
  class scale_y_continuous(scale):
      VALID_SCALES = ['name', 'labels', 'limits', 'breaks', 'trans']
      def __radd__(self, gg):
          gg = deepcopy(gg)
          if self.name:
              gg.ylab = self.name.title()
          if self.labels:
              if self.labels in LABEL_FORMATS:
                  format_func = LABEL_FORMATS[self.labels]
                  gg.ytick_formatter = FuncFormatter(format_func)
              else:
                  gg.ytick_labels = self.labels
          if self.limits:
              gg.ylimits = self.limits
          if self.breaks:
              gg.ybreaks = self.breaks
          return gg
  
  
subject: Update scale_y_continuous.py