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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 to_xdr_amount(value):
 """Converts an amount to the appropriate value to send over the network as a part of an XDR object. Each asset amount is encoded as a signed 64-bit integer in the XDR structures. An asset amount unit (that which is seen by end users) is scaled down by a factor of ten million (10,000,000) to arrive at the native 64-bit integer representation. For example, the integer amount value 25,123,456 equals 2.5123456 units of the asset. This scaling allows for seven decimal places of precision in human-friendly amount units. This static method correctly multiplies the value by the scaling factor in order to come to the integer value used in XDR structures. See `Stellar's documentation on Asset Precision <https://www.stellar.org/developers/guides/concepts/assets.html#amount-precision-and-representation>`_ for more information. :param str value: The amount to convert to an integer for XDR serialization. """

        if not isinstance(value, str):
            raise NotValidParamError("Value of type '{}' must be of type String, but got {}".format(value, type(value)))

        # throw exception if value * ONE has decimal places (it can't be
        # represented as int64)
        try:
            amount = int((Decimal(value) * ONE).to_integral_exact(context=Context(traps=[Inexact])))
        except decimal.Inexact:
            raise NotValidParamError("Value of '{}' must have at most 7 digits after the decimal.".format(value))
        except decimal.InvalidOperation:
            raise NotValidParamError("Value of '{}' must represent a positive number.".format(value))
        return amount