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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 renamecol(X, old, new):
 """ Rename column of a numpy ndarray with structured dtype, in-place. Implemented by the tabarray method :func:`tabular.tab.tabarray.renamecol`. **Parameters** **X** : numpy ndarray with structured dtype The numpy array for which a column is to be renamed. **old** : string Old column name, e.g. a name in `X.dtype.names`. **new** : string New column name to replace `old`. """

    NewNames = tuple([n if n != old else new for n in X.dtype.names])
    X.dtype.names = NewNames