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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 _norm_default(x):
 """Default Euclidean norm implementation."""

    # Lazy import to improve `import odl` time
    import scipy.linalg

    if _blas_is_applicable(x.data):
        nrm2 = scipy.linalg.blas.get_blas_funcs('nrm2', dtype=x.dtype)
        norm = partial(nrm2, n=native(x.size))
    else:
        norm = np.linalg.norm
    return norm(x.data.ravel())