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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 main():
 """ NAME gofish.py DESCRIPTION calculates fisher parameters from dec inc data INPUT FORMAT takes dec/inc as first two columns in space delimited file SYNTAX gofish.py [options] [< filename] OPTIONS -h prints help message and quits -i for interactive filename entry -f FILE, specify input file -F FILE, specifies output file name < filename for reading from standard input OUTPUT mean dec, mean inc, N, R, k, a95, csd """

    if '-h' in sys.argv: # check if help is needed
        print(main.__doc__)
        sys.exit() # graceful quit
    if '-i' in sys.argv: # ask for filename
        file=input("Enter file name with dec, inc data: ")
        f=open(file,'r')
        data=f.readlines()
    elif '-f' in sys.argv:
        dat=[]
        ind=sys.argv.index('-f')
        file=sys.argv[ind+1]
        f=open(file,'r')
        data=f.readlines()
    else:
        data = sys.stdin.readlines()  # read from standard input
    ofile = ""
    if '-F' in sys.argv:
        ind = sys.argv.index('-F')
        ofile= sys.argv[ind+1]
        out = open(ofile, 'w + a')
    DIs= [] # set up list for dec inc data
    for line in data:   # read in the data from standard input
        if '\t' in line:
            rec=line.split('\t') # split each line on space to get records
        else:
            rec=line.split() # split each line on space to get records
        DIs.append((float(rec[0]),float(rec[1])))
#
    fpars=pmag.fisher_mean(DIs)
    outstring='%7.1f %7.1f    %i %10.4f %8.1f %7.1f %7.1f'%(fpars['dec'],fpars['inc'],fpars['n'],fpars['r'],fpars['k'],fpars['alpha95'], fpars['csd'])
    if ofile == "":
        print(outstring)
    else:
        out.write(outstring+'\n')