code: def get_inasafe_default_value_qsetting(
          qsetting, category, inasafe_field_key):
      
      key = 'inasafe/default_value/%s/%s' % (category, inasafe_field_key)
      default_value = qsetting.value(key)
      if default_value is None:
          if category == GLOBAL:
              # If empty for global setting, use default one.
              inasafe_field = definition(inasafe_field_key)
              default_value = inasafe_field.get('default_value', {})
              return default_value.get('default_value', zero_default_value)
  
          return zero_default_value
      try:
          return float(default_value)
      except ValueError:
          return zero_default_value
docs: Helper method to get the inasafe default value from qsetting.
  
      :param qsetting: QSetting.
      :type qsetting: QSetting
  
      :param category: Category of the default value. It can be global or
          recent. Global means the global setting for default value. Recent
          means the last set custom for default value from the user.
      :type category: str
  
      :param inasafe_field_key: Key for the field.
      :type inasafe_field_key: str
  
      :returns: Value of the inasafe_default_value.
      :rtype: float