def is_number(var):
    """
    Determine if a variable contains a number.

    Args:
        var (str): The variable to test.

    Returns:
        result (bool): True if the values can be converted, False otherwise.

    Examples:
        >>> is_number('<100.0>')
        False
        >>> is_number('100.0+50j')
        True
        >>> is_number('1e3')
        True
    """
    try:
        complex(var)
    except (TypeError, ValueError):
        result = False
    else:
        result = True
    return result