How to use the azure-servicemanagement-legacy.azure.servicemanagement._http.winhttp.BSTR function in azure-servicemanagement-legacy

def set_request_header(self, name, value):
        ''' Sets the request header. '''

        _name = BSTR(name)
        _value = BSTR(value)
        _WinHttpRequest._SetRequestHeader(self, _name, _value)

def set_proxy_credentials(self, user, password):
        _WinHttpRequest._SetCredentials(
            self, BSTR(user), BSTR(password),
            HTTPREQUEST_SETCREDENTIALS_FOR_PROXY)

def open(self, method, url):
        '''
        Opens the request.

        method:
            the request VERB 'GET', 'POST', etc.
        url:
            the url to connect
        '''
        flag = VARIANT.create_bool_false()
        _method = BSTR(method)
        _url = BSTR(url)
        _WinHttpRequest._Open(self, _method, _url, flag)

def set_request_header(self, name, value):
        ''' Sets the request header. '''

        _name = BSTR(name)
        _value = BSTR(value)
        _WinHttpRequest._SetRequestHeader(self, _name, _value)

(1, 'AddRef')
    _Release = WINFUNCTYPE(c_long) \
        (2, 'Release')
    _SetProxy = WINFUNCTYPE(HRESULT,
                            HTTPREQUEST_PROXY_SETTING,
                            VARIANT,
                            VARIANT) \
        (7, 'SetProxy')
    _SetCredentials = WINFUNCTYPE(HRESULT,
                                  BSTR,
                                  BSTR,
                                  HTTPREQUEST_SETCREDENTIALS_FLAGS) \
        (8, 'SetCredentials')
    _Open = WINFUNCTYPE(HRESULT, BSTR, BSTR, VARIANT) \
        (9, 'Open')
    _SetRequestHeader = WINFUNCTYPE(HRESULT, BSTR, BSTR) \
        (10, 'SetRequestHeader')
    _GetResponseHeader = WINFUNCTYPE(HRESULT, BSTR, POINTER(c_void_p)) \
        (11, 'GetResponseHeader')
    _GetAllResponseHeaders = WINFUNCTYPE(HRESULT, POINTER(c_void_p)) \
        (12, 'GetAllResponseHeaders')
    _Send = WINFUNCTYPE(HRESULT, VARIANT) \
        (13, 'Send')
    _Status = WINFUNCTYPE(HRESULT, POINTER(c_long)) \
        (14, 'Status')
    _StatusText = WINFUNCTYPE(HRESULT, POINTER(c_void_p)) \
        (15, 'StatusText')
    _ResponseText = WINFUNCTYPE(HRESULT, POINTER(c_void_p)) \
        (16, 'ResponseText')
    _ResponseBody = WINFUNCTYPE(HRESULT, POINTER(VARIANT)) \
        (17, 'ResponseBody')
    _ResponseStream = WINFUNCTYPE(HRESULT, POINTER(VARIANT)) \

def create_bstr_from_str(text):
        variant = VARIANT()
        variant.vt = VT_BSTR
        variant.vdata.bstrval = BSTR(text)
        return variant

def __init__(self, value):
        super(BSTR, self).__init__(_SysAllocString(value))

MSDN exactly & it is only mapping the used fields.  Field names are also
    slighty different.
    '''

    class _tagData(Union):

        class _tagRecord(Structure):
            _fields_ = [('pvoid', c_void_p), ('precord', c_void_p)]

        _fields_ = [('llval', c_longlong),
                    ('ullval', c_ulonglong),
                    ('lval', c_long),
                    ('ulval', c_ulong),
                    ('ival', c_short),
                    ('boolval', c_ushort),
                    ('bstrval', BSTR),
                    ('parray', c_void_p),
                    ('record', _tagRecord)]

    _fields_ = [('vt', c_ushort),
                ('wReserved1', c_ushort),
                ('wReserved2', c_ushort),
                ('wReserved3', c_ushort),
                ('vdata', _tagData)]

    @staticmethod
    def create_empty():
        variant = VARIANT()
        variant.vt = VT_EMPTY
        variant.vdata.llval = 0
        return variant

def open(self, method, url):
        '''
        Opens the request.

        method:
            the request VERB 'GET', 'POST', etc.
        url:
            the url to connect
        '''
        flag = VARIANT.create_bool_false()
        _method = BSTR(method)
        _url = BSTR(url)
        _WinHttpRequest._Open(self, _method, _url, flag)