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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 eat_length(self, length):
 """Move current position forward by length and sets eos if needed."""

        pos = self.pos
        if self.eos or pos + length > self.length:
            return None

        col = self.col
        row = self.row
        for char in self.string[pos:pos + length]:
            col += 1
            pos += 1
            if char == '\n':  # handle a newline char
                col = 0
                row += 1

        self.pos = pos
        self.col = col
        self.row = row

        if not self.has_space():  # Set eos if there is no more space left.
            self.eos = 1