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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 wcxf2arrays_symmetrized(d):
 """Convert a dictionary with a Wilson coefficient name followed by underscore and numeric indices as keys and numbers as values to a dictionary with Wilson coefficient names as keys and numbers or numpy arrays as values. In contrast to `wcxf2arrays`, here the numpy arrays fulfill the same symmetry relations as the operators (i.e. they contain redundant entries) and they do not contain undefined indices. Zero arrays are added for missing coefficients."""

    C = wcxf2arrays(d)
    C = symmetrize_nonred(C)
    C = add_missing(C)
    return C