':arg stream: an `.IOStream`
:arg params: a `.HTTP1ConnectionParameters` or None
:arg context: an opaque application-defined object that is accessible
as ``connection.context``'

def __init__(self, stream, params=None, context=None):

    self.stream = stream
    if (params is None):
        params = HTTP1ConnectionParameters()
    self.params = params
    self.context = context
    self._serving_future = None
