\begin{tikzpicture}
                \coordinate (o) at (0,0);
                \coordinate (1) at (2,0);
                \coordinate (i) at (0,2);
                \coordinate (-1) at (-2,0); 
                \tkzDrawCircle[dashed,color=blue](o,1)
                \draw (-1)--(1);
                \draw (-2,0) arc(270:360:2cm);
                \draw (0,2) arc (180:270:2cm);
                \tkzDrawPoints[fill=white](1,-1,i)
                \tkzLabelPoints[right](1)
                \tkzLabelPoints[left](-1)
                \tkzLabelPoints[above](i)
\end{tikzpicture}