code: def get_dialect(self):
  		
  		if self.is_single_col:
  			return None
  
  		if self.delimiter and self.quotechar:
  			return Dialect(self.delimiter, self.quotechar,
  						True if self.escapechar is None else False,
  						self.escapechar)
  
  		ext = os.path.basename(self.file_path).rsplit('.', maxsplit=1)
  		ext = ext[1].lower() if len(ext) > 1 else None
  
  		if ext in TSV_EXTENSIONS:
  			self.delimiter = '\t'
  			self.quotechar = '"'
  
  		else:
  			f = self._open()
  			lines = f.read().splitlines()
  			f.close()
  
  			if lines:
  				dialect = self._determine_dialect(lines)
  			else:
  				dialect = None
  
  			if dialect is None:
  				self.is_single_col = True
  			else:
  				self.delimiter = dialect.delimiter
  				self.quotechar = dialect.quotechar
  				self.escapechar = dialect.escapechar
  
  		return self.get_dialect()
docs: Returns a Dialect named tuple or None if the dataset file comprises a
  		single column of data. If the dialect is not already known, then tries
  		to determine it. Raises ValueError if it fails in the latter case.