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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 as_wires(val, bitwidth=None, truncating=True, block=None):
 """ Return wires from val which may be wires, integers, strings, or bools. :param val: a wirevector-like object or something that can be converted into a Const :param bitwidth: The bitwidth the resulting wire should be :param bool truncating: determines whether bits will be dropped to achieve the desired bitwidth if it is too long (if true, the most-significant bits will be dropped) :param Block block: block to use for wire This function is mainly used to coerce values into WireVectors (for example, operations such as "x+1" where "1" needs to be converted to a Const WireVector). An example: :: def myhardware(input_a, input_b):
 a = as_wires(input_a) b = as_wires(input_b) myhardware(3, x) The function as_wires will covert the 3 to Const but keep `x` unchanged assuming it is a WireVector. """

    from .memory import _MemIndexed
    block = working_block(block)

    if isinstance(val, (int, six.string_types)):
        # note that this case captures bool as well (as bools are instances of ints)
        return Const(val, bitwidth=bitwidth, block=block)
    elif isinstance(val, _MemIndexed):
        # convert to a memory read when the value is actually used
        if val.wire is None:
            val.wire = as_wires(val.mem._readaccess(val.index), bitwidth, truncating, block)
        return val.wire
    elif not isinstance(val, WireVector):
        raise PyrtlError('error, expecting a wirevector, int, or verilog-style '
                         'const string got %s instead' % repr(val))
    elif bitwidth == '0':
        raise PyrtlError('error, bitwidth must be >= 1')
    elif val.bitwidth is None:
        raise PyrtlError('error, attempting to use wirevector with no defined bitwidth')
    elif bitwidth and bitwidth > val.bitwidth:
        return val.zero_extended(bitwidth)
    elif bitwidth and truncating and bitwidth < val.bitwidth:
        return val[:bitwidth]  # truncate the upper bits
    else:
        return val