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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 trim_decimals(s, precision=-3):
 """ Convert from scientific notation using precision """

        encoded = s.encode('ascii', 'ignore')
        str_val = ""
        if six.PY3:
            str_val = str(encoded, encoding='ascii', errors='ignore')[:precision]
        else:
            # If precision is 0, this must be handled seperately
            if precision == 0:
                str_val = str(encoded)
            else:
                str_val = str(encoded)[:precision]
        if len(str_val) > 0:
            return float(str_val)
        else:
            return 0