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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 _find_input_files(var, out):
 """Find input files within the given CWL object. """

    if isinstance(var, (list, tuple)):
        for x in var:
            out = _find_input_files(x, out)
    elif isinstance(var, dict):
        if var.get("class") == "File":
            out.append(var["path"])
            out = _find_input_files(var.get("secondaryFiles", []), out)
        for key, val in var.items():
            out = _find_input_files(val, out)
    return out