import hashlib


def is_placeholder_image(img_data):
	"""
	Checks for the placeholder image. If an imgur url is not valid (such as 
	http//i.imgur.com/12345.jpg), imgur returns a blank placeholder image. 

	@param: img_data (bytes) - bytes representing the image.

	@return: (boolean) True if placeholder image otherwise False
	"""
	sha256_placeholder = "9b5936f4006146e4e1e9025b474c02863c0b5614132ad40db4b925a10e8bfbb9"
	m = hashlib.sha256()
	m.update(img_data)
	return 	m.hexdigest() == sha256_placeholder