'Try to guess if the file is a CEL file.
>>> from galaxy.datatypes.sniff import get_test_fname
>>> fname = get_test_fname(\'test.CEL\')
>>> Cel().sniff(fname)
True
>>> fname = get_test_fname(\'drugbank_drugs.mz5\')
>>> Cel().sniff(fname)
False'

def sniff(self, filename):

    try:
        header = open(filename, 'rb').read(4)
        if (header == ';\x01\x00\x00'):
            return True
        return False
    except:
        return False
