regex to find exact nucleotide sequence

Question

I want to extract exact nucleotide sequence ("GATCGGAAGAGCTCGTATGCCGTCTTCTGCTTGAAA") where ever it occurs in file, using regex in python from a fastq file(where every second line after the line starting with @ is a nucleotide sequence ). this is the code I tried

import re
with open('last_mock.fastq','r') as rf:

    for line in rf:
        x= re.match( r"(GATCGGAAGAGCTCGTATGCCGTCTTCTGCTTGAAA)",line)
        if x:
             print(x)

this is the content of file:

       @HWUSI-EAS570R_0003:2:50:5038:17424#0/1
       CAGCTTCTGTTGATGCTGATTTAATTCCTGCAACTA
       +HWUSI-EAS570R_0003:2:50:5038:17424#0/1
       hhhhhhhhhhhgghhhhhahhhhhhhhhhhhgfhh[
       @HWUSI-EAS570R_0003:2:50:5175:17417#0/1
      CACCTTGCTTTATGGGAAAGCGTAACATAACTACAG
      +HWUSI-EAS570R_0003:2:50:5175:17417#0/1
      hhhhhhhhhhhfhhhhfaehhhhgahehhcghhfch
      @HWUSI-EAS570R_0003:2:50:5442:17417#0/1
      AGTTCGCCGACGTTTACGCCGCCTCGGTCCTCGGCA
      +HWUSI-EAS570R_0003:2:50:5442:17417#0/1
     ghhhhhhhhhhhhhhfhhhhhhhfhhgfhhgfgffc
     @HWUSI-EAS570R_0003:2:50:5552:17421#0/1
     AAGACATCAAACTACGAAACTACTACAAGAAAACAT
     +HWUSI-EAS570R_0003:2:50:5552:17421#0/1
    hghghhhhhhhhhghhhhhhghhhhhehhhhheg`h
    @HWUSI-EAS570R_0003:2:50:5658:17415#0/1
    GTTCAAGTGATTCTCCTGCCTCAGCCTCCTGAGTAG
   +HWUSI-EAS570R_0003:2:50:5658:17415#0/1
   hhhhhfhghdhhhhhhhhhhhgghhfheffhdfcbf
   @HWUSI-EAS570R_0003:2:50:5712:17421#0/1
   TTTCTTTTACCCCTAATCCTATCAGCTTTTTCTCCC
  +HWUSI-EAS570R_0003:2:50:5712:17421#0/1
  hhhghhhhhhhhhhhhhhghhhghhhhhghhhghhh

`re.match` only searches at the start of string, use `re.search`. Also, you need `print(x.group())`, not `print(x)`. To get all matches use `re.findall`. — Wiktor Stribiżew, Aug 27 '21 at 09:45
yes ```re.search``` or ```re.findall``` (```re.findall``` returns list) — Ghost Ops, Aug 27 '21 at 09:46

regex to find exact nucleotide sequence

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