def get_shape_from_dim(L, axis_0, axis_1=None):
    """
        Constructs a chain shape tuple of length L with constant site dimensions everywhere
    :param L: Length of chain
    :param axis_0: Dimension of the first leg on each site (axis 0) as integer
    :param axis_1: Dimension of the second leg on each site (axis 1) as integer
    :return: chain shape tuple
    """
    if axis_1 is None:
        return tuple([(axis_0, )] * L)
    else:
        return tuple([(axis_0, axis_1)] * L)