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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 rpyhttp(value):
 """ converts a no namespace pyuri back to a standard uri """

        if value.startswith("http"):
            return value
        try:
            parts = value.split("_")
            del parts[0]
            _uri = base64.b64decode(parts.pop(0)).decode()
            return _uri + "_".join(parts)
        except (IndexError, UnicodeDecodeError, binascii.Error):
            # if the value is not a pyuri return the value
            return value