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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 encode(self, boundary):
 """Returns the string encoding of this parameter"""

        if self.value is None:
            value = self.fileobj.read()
        else:
            value = self.value

        if re.search("^--%s$" % re.escape(boundary), value, re.M):
            raise ValueError("boundary found in encoded string")

        return "%s%s\r\n" % (self.encode_hdr(boundary), value)