def is_informational_response(headers):
    for n, v in headers:
        if isinstance(n, bytes):
            sigil = b':'
            status = b':status'
            informational_start = b'1'
        else:
            sigil = u':'
            status = u':status'
            informational_start = u'1'

        # If we find a non-special header, we're done here: stop looping.
        if not n.startswith(sigil):
            return False

        # This isn't the status header, bail.
        if n != status:
            continue

        # If the first digit is a 1, we've got informational headers.
        return v.startswith(informational_start)
Searches a header block for a :status header to confirm that a given
dataset/ETHPy150Open python-hyper/hyper-h2/h2/utilities.py/is_informational_response