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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 readCovariatesFile(fFile):
 """" reading in covariate file cfile file containing the fixed effects as NxP matrix (N=number of samples, P=number of covariates) """

    assert os.path.exists(fFile), '%s is missing.'%fFile
    F = SP.loadtxt(fFile)
    if F.ndim==1: F=F[:,SP.newaxis]
    return F