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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _parse_url(host, provided_protocol=None):
 """ Process the provided host and protocol to return them in a standardized way that can be subsequently used by Cytomine methods. If the protocol is not specified, HTTP is the default. Only HTTP and HTTPS schemes are supported. Parameters host: str The host, with or without the protocol provided_protocol: str ("http", "http://", "https", "https://") The default protocol - used only if the host value does not specify one Return ------ (host, protocol):
 tuple The host and protocol in a standardized way (host without protocol, and protocol in ("http", "https")) Examples -------- ("localhost-core", "http") ("demo.cytomine.coop", "https") """

        protocol = "http" # default protocol
        
        if host.startswith("http://"):
            protocol = "http"
        elif host.startswith("https://"):
            protocol = "https"
        elif provided_protocol is not None:
            provided_protocol = provided_protocol.replace("://", "")
            if provided_protocol in ("http", "https"):
                protocol = provided_protocol
        
        host = host.replace("http://", "").replace("https://", "")
        if host.endswith("/"):
            host = host[:-1]

        return host, protocol