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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 convert(self, value, param, ctx):
 # pylint: disable=inconsistent-return-statements """Validate memory argument. Returns the memory value in megabytes."""

        matches = MEMORY_RE.match(value.lower())
        if matches is None:
            self.fail('%s is not a valid value for memory amount' % value, param, ctx)
        amount_str, unit = matches.groups()
        amount = int(amount_str)
        if unit in [None, 'm', 'mb']:
            # Assume the user intends gigabytes if they specify a number < 1024
            if amount < 1024:
                return amount * 1024
            else:
                if amount % 1024 != 0:
                    self.fail('%s is not an integer that is divisable by 1024' % value, param, ctx)
                return amount
        elif unit in ['g', 'gb']:
            return amount * 1024