Check numers in Python

gistfile1.py

def isfloat(x):
    try:
        a = float(x)
    except ValueError:
        return False
    else:
        return True

def isint(x):
    try:
        a = float(x)
        b = int(a)
    except ValueError:
        return False
    else:
        return a == b


def check_type(s):
    """Check the type of a string passed"""
    #define the possible types
    o_str, o_int = type('a'),type(1)
    o_float, o_list, o_null=type(1.1), type([]), type(None)
    if s[0]=="{": return o_list
    elif (s=='NULL') | (s==""): return o_null
    elif isfloat(s) : return o_float
    elif isint(s) : return o_int
    else: return o_str