def public_key_to_xrb_address(public_key):
    """
    Convert `public_key` (bytes) to an xrb address

    >>> public_key_to_xrb_address(b'00000000000000000000000000000000')
    'xrb_1e3i81r51e3i81r51e3i81r51e3i81r51e3i81r51e3i81r51e3imxssakuq'

    :param public_key: public key in bytes
    :type public_key: bytes

    :return: xrb address
    :rtype: str
    """

    if not len(public_key) == 32:
        raise ValueError('public key must be 32 chars')

    padded = b'000' + public_key
    address = b32xrb_encode(padded)[4:]
    checksum = b32xrb_encode(address_checksum(public_key))
    return 'xrb_' + address.decode('ascii') + checksum.decode('ascii')