Compute MD5 hash on passed file and return results in a tuple of values.

    :type fp: file
    :param fp: File pointer to the file to MD5 hash.  The file pointer
               will be reset to its current location before the
               method returns.

    :type buf_size: integer
    :param buf_size: Number of bytes per read request.

    :type size: int
    :param size: (optional) The Maximum number of bytes to read from
                 the file pointer (fp). This is useful when uploading
                 a file in multiple parts where the file is being
                 split inplace into different parts. Less bytes may
                 be available.

    :rtype: tuple
    :return: A tuple containing the hex digest version of the MD5 hash
             as the first element, the base64 encoded version of the
             plain digest as the second element and the data size as
             the third element.

def compute_md5(fp, buf_size=8192, size=None):
    """
    Compute MD5 hash on passed file and return results in a tuple of values.

    :type fp: file
    :param fp: File pointer to the file to MD5 hash.  The file pointer
               will be reset to its current location before the
               method returns.

    :type buf_size: integer
    :param buf_size: Number of bytes per read request.

    :type size: int
    :param size: (optional) The Maximum number of bytes to read from
                 the file pointer (fp). This is useful when uploading
                 a file in multiple parts where the file is being
                 split inplace into different parts. Less bytes may
                 be available.

    :rtype: tuple
    :return: A tuple containing the hex digest version of the MD5 hash
             as the first element, the base64 encoded version of the
             plain digest as the second element and the data size as
             the third element.
    """
    m = md5()
    spos = fp.tell()
    if size and size < buf_size:
        s = fp.read(size)
    else:
        s = fp.read(buf_size)
    while s:
        m.update(s)
        if size:
            size -= len(s)
            if size <= 0:
                break
        if size and size < buf_size:
            s = fp.read(size)
        else:
            s = fp.read(buf_size)
    hex_md5 = m.hexdigest()
    base64md5 = base64.encodestring(m.digest())
    if base64md5[-1] == '\n':
        base64md5 = base64md5[0:-1]
    # data_size based on bytes read.
    data_size = fp.tell() - spos
    fp.seek(spos)
    return (hex_md5, base64md5, data_size)