def bytes_to_int(src):
    """
    Reinterpret byte array as a big-endian integer.

    Arguments
    ---------
    src : bytes
        Byte array representation of a number.

    Returns
    -------
    int
        The integer value of that number.
    """
    ival = 0
    for bval in src:
        ival <<= 8
        ival |= bval
    return ival