# [Python 3], <s>56</s> 53 bytes

<!-- language-all: lang-python -->

    m=int(input())
    a=b=1
    while a<m:b,a=a,a+b
    print(a==m) 

[Try it online!][TIO-j46kjzpc]

[Python 3]: https://docs.python.org/3/
[TIO-j46kjzpc]: https://tio.run/##K6gsycjPM/7/P9c2M69EIzOvoLREQ1OTK9E2ydaQqzwjMydVIdEm1ypJJ9E2USdRO4mroAikMNHWNldT4f9/C0sA "Python 3 – Try It Online"