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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 is_fasta(filename):
 """Check if filename is FASTA based on extension Return: Boolean """

    if re.search("\.fa*s[ta]*$", filename, flags=re.I):
        return True
    elif re.search("\.fa$", filename, flags=re.I):
        return True
    else:
        return False