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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 find_function(self, name):
 """Find the Function by its name."""

        deffunction = lib.EnvFindDeffunction(self._env, name.encode())
        if deffunction == ffi.NULL:
            raise LookupError("Function '%s' not found" % name)

        return Function(self._env, deffunction)