def connection_from_context(
        self, request_context: dict[str, typing.Any]
    ) -> HTTPConnectionPool:
        """
        Get a :class:`urllib3.connectionpool.ConnectionPool` based on the request context.

        ``request_context`` must at least contain the ``scheme`` key and its
        value must be a key in ``key_fn_by_scheme`` instance variable.
        """
        if "strict" in request_context:
            warnings.warn(
                "The 'strict' parameter is no longer needed on Python 3+. "
                "This will raise an error in urllib3 v2.1.0.",
                DeprecationWarning,
            )
            request_context.pop("strict")

        scheme = request_context["scheme"].lower()
        pool_key_constructor = self.key_fn_by_scheme.get(scheme)
        if not pool_key_constructor:
            raise URLSchemeUnknown(scheme)
        pool_key = pool_key_constructor(request_context)

        return self.connection_from_pool_key(pool_key, request_context=request_context)

        Get a :class:`urllib3.connectionpool.ConnectionPool` based on the request context.

        ``request_context`` must at least contain the ``scheme`` key and its
        value must be a key in ``key_fn_by_scheme`` instance variable.
        
src/urllib3/poolmanager.py