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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 input_file(self, _container):
 """Find the input path of a uchroot container."""

        p = local.path(_container)
        if set_input_container(p, CFG):
            return

        p = find_hash(CFG["container"]["known"].value, container)
        if set_input_container(p, CFG):
            return

        raise ValueError("The path '{0}' does not exist.".format(p))