def Skin(CASRN, AvailableMethods=False, Method=None):  
def list_methods():<EOL><INDENT>methods = []<EOL>if CASRN in _OntarioExposureLimits:<EOL><INDENT>methods.append(ONTARIO)<EOL><DEDENT>methods.append(NONE)<EOL>return methods<EOL><DEDENT>if AvailableMethods:<EOL><INDENT>return list_methods()<EOL><DEDENT>if not Method:<EOL><INDENT>Method = list_methods()[<NUM_LIT:0>]<EOL><DEDENT>if Method == ONTARIO:<EOL><INDENT>_Skin = (_OntarioExposureLimits[CASRN]["<STR_LIT>"])<EOL><DEDENT>elif Method == NONE:<EOL><INDENT>_Skin = None<EOL><DEDENT>else:<EOL><INDENT>raise Exception('<STR_LIT>')<EOL><DEDENT>return _Skin<EOL>
This function handles the retrieval of whether or not a chemical can
    be absorbed through the skin, relevant to chemical safety calculations.

    This API is considered experimental, and is expected to be removed in a
    future release in favor of a more complete object-oriented interface.

    >>> Skin('108-94-1')
    True
    >>> Skin('1395-21-7')
    False
    >>> Skin('7572-29-4', AvailableMethods=True)
    ['Ontario Limits', 'None']