(x)
return RSA.number.bytes_to_long(x)
Accepts a byte string as input parameter and return the associated long
    value:

    Input : x        octet string to be converted

    Output: x        corresponding nonnegative integer

    Reverse function is pkcs_i2osp()
Accepts a byte string as input parameter and return the associated long
    value:
Accepts a byte string as input parameter and return the associated long value :
def pkcs_os2ip(x):
    """
    Accepts a byte string as input parameter and return the associated long
    value:

    Input : x        octet string to be converted

    Output: x        corresponding nonnegative integer

    Reverse function is pkcs_i2osp()
    """
    return RSA.number.bytes_to_long(x)
def pkcs_os2ip ( x ) : return RSA . number . bytes_to_long ( x )