old_contents: 
  import os.path
  from yaml import load
  from yaml.scanner import ScannerError
  from errors import ConfigFileSyntaxError
  try:
      from yaml import CLoader as Loader
  except ImportError:
      from yaml import Loader
  
  
  # def _normalize(content):
  #     return content.replace('\t', ' ')
  
  
  def pre_process(data, macros):
      if callable(macros):
          macros = macros()
      return data % macros
  
  
  def load_string(str_data, macros=None):
      if macros:
          str_data = pre_process(str_data, macros)
      return load(str_data, Loader)
  
  
  def load_yaml(file_path, macros=None):
      stream = open(file_path)
      file_dir = os.path.abspath(os.path.dirname(file_path))
      macros = {} if macros is None else macros
      macros.update(here=file_dir)
      try:
          return load_string(stream.read(), macros)
      except ScannerError as ex:
          raise ConfigFileSyntaxError(file_path, ex)
      finally:
          stream.close()
  
  
new_contents: 
  import os.path
  from yaml import load
  from yaml.scanner import ScannerError
  from pymlconf.errors import ConfigFileSyntaxError
  try:
      from yaml import CLoader as Loader
  except ImportError:
      from yaml import Loader
  
  
  # def _normalize(content):
  #     return content.replace('\t', ' ')
  
  
  def pre_process(data, macros):
      if callable(macros):
          macros = macros()
      return data % macros
  
  
  def load_string(str_data, macros=None):
      if macros:
          str_data = pre_process(str_data, macros)
      return load(str_data, Loader)
  
  
  def load_yaml(file_path, macros=None):
      stream = open(file_path)
      file_dir = os.path.abspath(os.path.dirname(file_path))
      macros = {} if macros is None else macros
      macros.update(here=file_dir)
      try:
          return load_string(stream.read(), macros)
      except ScannerError as ex:
          raise ConfigFileSyntaxError(file_path, ex)
      finally:
          stream.close()
  
subject: change errors import in yaml_helper module to be absolute (python 3 compatibility) - closes #14