Cast CamelCase to "underscore_case"

main_re.py

import re

def _camel_to_underscore_case(name):
    """
    Translate 'CamelCaseNames' to 'camel_case_names'.
    """
    camelcase_boundry = '((?<=[a-z])[A-Z])'
    return re.sub(camelcase_boundry, '_\\1', name).lower()

def camel_to_underscore_case(obj, deep=True):
    if isinstance(obj, dict):
        return dict((_camelcase_to_spaces(k),
                     camel_to_underscore_case(v, deep) if deep else v)
                    for k,v in obj.iteritems())
    elif deep and isinstance(obj, list):
        return map(lambda x: camel_to_underscore_case(x, deep))
    else:
        return obj

if __name__ == "__main__":
    values = [
            {"IsCustomer": True, "OBID": 12345},
            {"isCustomer": True, "obid": 12345},
            {"iscustomer": True, "obid": 12345},
            {"is_customer": True, "obid": 12345},
            {"isCustomer": True, "oBiD": 12345},
            {"isCustomer": True, "Obid": 12345},
            {"obj": {"isCustomer": True, "Obid": 12345}}
    ]

    for val in values:
        print "-------------"
        print val
        print "->"
        print camel_to_underscore_case(val)