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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 _ctypes_clean(parameter):
 """Returns the lines of code required to assign the correct values to the integers representing the indices of the output arrays in the ctypes wrapper subroutine. """

    if ("out" in parameter.direction and parameter.dimension is not None
        and ":" in parameter.dimension and ("pointer" in parameter.modifiers or
                                            "allocatable" in parameter.modifiers)):
        params = parameter.ctypes_parameter()
        result = []
        spacer = "    "
        #We get segfaults if we try to assign c-pointers to unallocated pointers or arrays.
        if "optional" in parameter.modifiers:
            if "pointer" in parameter.modifiers:
                result.append("{}if (associated({})) then".format(spacer, parameter.name))
                spacer += "  "
            elif "allocatable" in parameter.modifiers:
                result.append("{}if (allocated({})) then".format(spacer, parameter.name))
                spacer += "  "

        #We have to copy the values or at least update the pointer to access the
        #variables with 'target' and 'save' attributes.
        result.append("{0}{1}_t = {1}".format(spacer, parameter.name))
            
        if parameter.direction == "(inout)":
            result.append("{1}{0}_o = C_LOC({0}_t)".format(parameter.name, spacer))
            #Update the index variables for the dimensions of the output variable.
            for i, p in enumerate(params[1:-1]):
                result.append("{}{} = size({}, {})".format(spacer, p, parameter.name, i+1))
        else:
            #This is the case for intent(out)
            result.append("{1}{0}_c = C_LOC({0}_t)".format(parameter.name, spacer))
            for i, p in enumerate(params[1::]):
                result.append("{}{} = size({}, {})".format(spacer, p, parameter.name, i+1))

        if ("optional" in parameter.modifiers and
            ("pointer" in parameter.modifiers or "allocatable" in parameter.modifiers)):
            result.append("    end if")

        return ('\n'.join(result), True)
    elif parameter.dtype == "logical" and "out" in parameter.direction:
        return ("    {0}_c = {0}".format(parameter.name), False)