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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 clean(amount):
 """ Converts a number to a number with decimal point. :param str amount: The input number. :rtype: str """

        # Return empty input immediately.
        if not amount:
            return amount

        if re.search(r'[\. ][0-9]{3},[0-9]{1,2}$', amount):
            # Assume amount is in 1.123,12 or 1 123,12 format (Dutch).
            return amount.replace('.', '').replace(' ', '').replace(',', '.')

        if re.search(r'[, ][0-9]{3}\.[0-9]{1,2}$', amount):
            # Assume amount is in 1,123.12 format (Engels).
            return amount.replace(',', '').replace(' ', '')

        if re.search(r'[0-9](,[0-9]{1,2}$)', amount):
            # Assume amount is in 123,12 or in 123,1 format (Dutch).
            return amount.replace(',', '.')

        # Format of amount is not recognized. Return amount.
        return amount