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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 format_float_field(__, prec, number, locale):
 """Formats a fixed-point field."""

    format_ = u'0.'
    if prec is None:
        format_ += u'#' * NUMBER_DECIMAL_DIGITS
    else:
        format_ += u'0' * int(prec)
    pattern = parse_pattern(format_)
    return pattern.apply(number, locale)