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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 fix_variable(self, v, value):
 """Fix the value of a variable and remove it from a binary quadratic model. Args: v (variable):
 Variable in the binary quadratic model to be fixed. value (int):
 Value assigned to the variable. Values must match the :class:`.Vartype` of the binary quadratic model. Examples: This example creates a binary quadratic model with one variable and fixes its value. 0.5 1.0 False """

        adj = self.adj
        linear = self.linear

        if value not in self.vartype.value:
            raise ValueError("expected value to be in {}, received {} instead".format(self.vartype.value, value))

        removed_interactions = []
        for u in adj[v]:
            self.add_variable(u, value * adj[v][u])
            removed_interactions.append((u, v))
        self.remove_interactions_from(removed_interactions)

        self.add_offset(value * linear[v])
        self.remove_variable(v)