def read_file_in_lines(filename):
	"""
	Reads a file into lines.
	
	:param filename: the filename of the file to be read.
	:returns: a list with the lines of the file.
	"""
	lines = []
	with open(filename) as infile:
		for line in infile:
			line = line.strip()
			if line and not line.startswith('#'):
				lines.append(line)
	return lines