def convert_number(string):
    """Convert a string to number
    If int convert to int otherwise float
    
    If not possible return None
    """
    res = None
    if isint(string):
        res = int(string)
    elif isfloat(string):
        res = float(string) 
    return res
Convert a string to number
    If int convert to int otherwise float
    
    If not possible return None